REPO Mutant Enemies

Rarely, a vanilla R.E.P.O. enemy spawns mutated — it keeps the base enemy's model but glows with a coloured mutation aura and gains a new, nastier ability. Version 1.1 includes 28 mutants.

⚠ Everyone in the lobby must install this mod (not just the host) — it's the only way for every player to see the mutation auras and visuals correctly.

Mutants

• Boomday Boy (mutated Birthday Boy, orange aura): a tougher Birthday Boy that periodically sets off an explosion when a player gets close — and survives it, re-arming after a cooldown. Its balloons are tinted orange as a warning:
  • A player touching a balloon explodes only that balloon — no chain reaction.
  • An enemy brushing a balloon just pops it harmlessly.
  • When the Boomday Boy dies (or blasts on its recurring fuse), every balloon it placed detonates in the order it placed them, one every 0.1s — a rolling chain reaction.
  • Multiple Boomday Boys each track their own balloons independently.
• Poltergeist (mutated Mentalist, light-blue aura): its anti-gravity power runs wild. It projects a persistent zero-G field that makes nearby valuables, props and the cart float, and it periodically hurls a floating valuable at a player using the same throw physics as the game's own loot-throwing enemy. Its stronger field periodically inverts into high gravity, slamming players and everything it was floating back into the floor; anyone still inside takes a final impact hit.
• Meltdown Crew (mutated Cleanup Crew, toxic-green aura): instead of a single bomb-head, it launches three heads at once — one at normal speed, one sluggish, and one frantic — all chasing at the same time, then detonating together.
• Snatcher (mutated Hidden, violet aura): normally, Hidden grabs a player and slowly drags them far away on foot before letting go. The Snatcher skips the walk — the instant it grabs a player, it teleports them straight to a random spot on the map (checked to be solid ground, never a pit or void) and damages them on the spot. It no longer leaves a delayed bomb at the destination.
• Deathgaze (mutated Peeper, red aura): its stare isn't just uncomfortable anymore. Break line of sight before it locks onto you for too long. If the stare stays unbroken after its first beam, every follow-up beam charges faster until you finally escape its gaze.
• Deadeye (mutated Huntsman, blue aura): it's got its hands on your Photon Blaster. When it shoots, so does the blaster — a sustained laser beam with an explicit, once-per-beam line hit (not visual-only).
• Trickster (mutated Gnome, purple aura): a MIMIC. When things go quiet it disguises itself as a random valuable — and while disguised, even its aura goes dark. Get close, grab it, or hit it, and the treasure bursts back into a gnome already lunging at you. A vanilla four-Gnome squad shares one mutation roll, so all four become Tricksters together. Killing one splits it into two real Gnomes once per life; those children cannot split again until a genuine respawn resets the rule.
• Big Bang (mutated Banger, fiery-orange aura): twice the size, and it roams in a configurable squad. Each one goes out with a full shop-grenade blast, and one blast sets off the next...
• Glutton (mutated Animal, amber aura): it EATS your loot — any loose valuable it gets close to is swallowed whole. And every meal makes it tougher, harder-hitting and heavier. Kill it and it coughs the whole haul back up.
• Alpha (mutated Apex Predator, gold aura): a countdown ticks over its head — at zero it transforms, trades places with a random other enemy on the map, and HOWLS: everything alive hunts you for a while.
• Belladonna (mutated Bella, magenta aura): every bell tell magnetises nearby real valuables into a short cursed orbit, then fires them at her target one after another with boosted impact damage. She also escalates to attacks much faster than vanilla and holds a grudge longer.
• Flambé (mutated Chef, burning-orange aura): flings four REAL armed shop grenades around itself each tumble attack. The grenades can't hurt enemies — only you.
• Fenrir (mutated Elsa, icy-blue aura): the dog freezes and a countdown ticks over its head the moment it spots you. When it hits zero it transforms and hunts you as normal. Just enough time to run — petting won't help. Staying close is no longer safe: the transformation releases a damaging shockwave.
• Redline (mutated Reaper, hot-red aura): records its exact path during an overclocked chase. When it attacks, the path lights up and a lethal red pulse replays the route from oldest point to newest.
• Singularity (mutated Bowtie, ultraviolet aura): its yell becomes a visible gravity well that drags players inward while real valuables orbit it. When the yell stops, all captured debris is slingshotted at players with boosted physical impact damage.
• Faultline (mutated Headman, molten-amber aura): each mace wind-up tears a glowing three-way fracture through the floor. After its warning, all three branches remain dangerous for several seconds.
• Kaleidoscope (mutated Clown, electric-cyan aura): its laser impact splits into three prismatic blast marks across the floor. The rings give you a moment to move before all three detonate.
• House Edge (mutated Gambit, casino-gold aura): every roulette colour adds a different room-wide house rule: Red Light punishes movement, Yellow confiscates held loot, Green heals/shields enemies, White repeatedly launches players, and Black shuffles player positions.
• Resonance (mutated Upscream, resonant-blue aura): its attack marks nearby players with a returning echo. You must become still before the countdown ends; anyone still moving when the echo returns is hit.
• Blood Bank (mutated Tick, transfusion-green aura): every bite shares part of the health it steals with all nearby wounded enemies and temporarily shields every nearby enemy against damage. Focus it first or the whole room becomes harder to kill.
• Railgun (mutated Rugrat, charged-cyan aura): turns every valuable it throws into a glowing, high-speed projectile with a stronger impact. The bright trail shows exactly what is about to hit you.
• Blackout (mutated Robe, near-black violet aura): when it starts hunting, nearby room lights and carried lights fade almost completely — and the Robe speeds up inside its own darkness. The lights and movement speed recover when it calms down or moves away.
• Contagion (mutated Spewer, toxic-green aura): each puke episode infects nearby loose valuables. Infected loot glows green; grabbing it triggers a one-shot toxic backlash before the infection clears.
• Necromancer (mutated Head Grabber, soul-violet aura): stealing a death head chains every exposed player nearby to that head. Hold real cover long enough to sever the chain, or the completed ritual damages you, tears away your held object and violently recalls you toward the head.
• Heartbreak (mutated Heart Hugger, hostile-pink aura): its chomp forges visible chains between player pairs. Partners must physically reunite and hold contact to break them; an unpaired player must reach a phantom heart. Unresolved chains pulse, pull and finally snap.
• Deathlight (mutated Oogly, searchlight-red aura): its hostile spotlight photographs a player's exact position. Break line of sight behind real cover long enough to erase the image, or be damaged and forcibly rewound to the glowing snapshot.
• Aftershock (mutated Shadow Child, electric-violet aura): each slap raises two enormous shadow walls around a forward corridor. They close into a final clap; escape sideways before they meet or be damaged, disarmed and thrown out of the lane.
• Parallax (mutated Thin Man, phase-cyan aura): every teleport leaves two temporary linked gates at its exact departure and arrival points. Players and loose loot entering either portal emerge from the other with a phase launch, turning the room itself into a dangerous traversal puzzle.

Grab a mutant and its name shows up, so you always know what you're dealing with.

How it works

• On spawn, a vanilla enemy has a chance to mutate: 2.5% per level, capped at 25% per mutant type (both configurable), rolled independently per type — so deeper runs get wilder.
• On displayed levels 5, 10, 15, ..., every enabled supported enemy is guaranteed to mutate. The interval is configurable; DisabledMutants is still respected.
• Once a specific enemy mutates, it stays mutated for the rest of the level, even if it despawns and respawns later.
• Mutants start with the configured health multiplier (2x by default), then gain +0.05x health per completed level, capped at 3.5x by default.
• Every client decides mutation independently (from a deterministic per-enemy, per-type roll), so the decision itself needs no network message. Ability events use the enemy's existing PhotonView; health, spawning and loose-world physics stay host-driven, while area damage is created locally on every client to match R.E.P.O.'s victim-authoritative damage rules.
• Explosions deal proper damage, knockback and sound.

Config & debug

BepInEx/config/com.matsu.repomutations.cfg

• Mutation / ChancePerLevel (2.5%/level), HealthMultiplier (mutants have 2x HP), aura light range/intensity
• Mutation / HealthBonusPerLevel (+0.05x per completed level), MaxHealthMultiplier (3.5x), GuaranteedSurgeInterval (default 5), DisabledMutants (comma-separated names to turn off)
• Balance revision 2 automatically raises both original and temporarily lowered defaults to the stronger preset. Values you customized yourself are preserved.
• Per-mutant tuning (damage, cooldowns, ranges, beam/fuse durations, countdowns, trail lifetime, squad size, Glutton growth rates, route replay, orbital debris, persistent cracks, roulette rules, Resonance stillness timing, Contagion traps, Blood Bank healing, Railgun projectiles, Deathgaze repeat charge, Fenrir shockwaves, Blood Bank shielding, Blackout radius/speed, Necromancer soul recalls, Heartbreak chains, Deathlight rewinds, Aftershock claps and Parallax gates.)
• Debug spawn keys (host only): F9 = Boomday Boy, F10 = Poltergeist, F8 = Meltdown Crew, F7 = Snatcher, F6 = Deathgaze, F5 = Deadeye, F4 = Trickster, F3 = Big Bang, F2 = Fenrir, F1 = Glutton, F11 = Alpha, F12 = Belladonna, Insert = Flambé, Home = Redline, Delete = Singularity, PageUp = Faultline, End = Kaleidoscope, PageDown = House Edge, Pause = Resonance, [ = Blood Bank, ] = Railgun, Backslash = Blackout, ; = Contagion, Quote = Necromancer, , = Heartbreak, . = Deathlight, / = Aftershock, BackQuote = Parallax

Bug reports & requests

Found a bug or have an idea? Please use this form: https://docs.google.com/forms/d/e/1FAIpQLSfl7f-oNiwjXjd7mUkfQoqBIhbJhQhhfV-ZmovjJVQ9orwuYQ/viewform

REPO Mutant Enemies（日本語）

R.E.P.O. のバニラ敵が、まれに突然変異してスポーンします。見た目はベース敵のモデルのままですが、 色つきの変異オーラをまとい、より厄介な新しい能力を得ます。v1.1では全28種です。

⚠ このMODはロビー全員が導入する必要があります（ホストのみでは不可）。全員が変異オーラや挙動を 正しく見るために必要です。

変異個体

• Boomday Boy（突然変異した Birthday Boy／オレンジのオーラ）: 通常より頑丈な Birthday Boy。プレイヤー が近づくと爆発を起こし、しかも自分は生き残ってクールダウン後にまた爆発します。風船は警告として オレンジ色に変異します:
  • プレイヤーが風船に触れるとその風船だけが爆発します（連鎖なし）。
  • 敵が風船に触れると連鎖もダメージもなく、ただ割れるだけです。
  • Boomday Boy が死亡（または周期爆発）すると、設置した風船が設置した順番に0.1秒間隔で次々に 爆発する連鎖反応が起きます。
  • 複数の Boomday Boy がいる場合、それぞれ自分の風船だけを個別に管理します。
• Poltergeist（突然変異した Mentalist／メンタリスト／水色のオーラ）: 反重力の力が暴走。周囲に持続する 無重力フィールドを張り、近くの宝・小物・カートをふわふわ浮かせ、周期的に浮いた宝をプレイヤーに ブン投げます。さらに強化されたフィールドが周期的に高重力へ反転し、浮かせていたプレイヤーと物体を 一気に床へ叩き落とし、範囲内に残ったプレイヤーへ最後の着地ダメージを与えます。
• Meltdown Crew（突然変異した Cleanup Crew／掃除屋／毒々しい緑のオーラ）: 爆弾頭を1つ投げる通常とは 違い、頭を3個同時に射出してきます — 通常速度・鈍足・凶暴な倍速の3つが同時に迫り、まとめて爆発します。
• Snatcher（突然変異した Hidden／隠れ者／紫のオーラ）: 通常のHiddenはプレイヤーを掴むと徒歩でゆっくり 遠くまで連れ去ってから離します。Snatcherは連れ去りを省略し、掴んだプレイヤーをその瞬間にマップ中の ランダムな地点へ瞬間移動させ（足がつく安全な地面だけを選ぶよう検証済み、奈落には飛ばされません）、 その場でダメージを与えます。転送先へ時限爆弾や裂け目は残しません。
• Deathgaze（突然変異した Peeper／覗き魔／赤いオーラ）: その視線はもう不快なだけでは済みません。長く ロックオンされる前に、視線を切りましょう。一度撃たれても同じ視線を切れないと、次のビームは 回を追うごとに短時間でチャージされます。
• Deadeye（突然変異した Huntsman／青いオーラ）: プレイヤーのPhoton Blasterを手に入れています。撃つとき、 ブラスターも一緒に火を噴きます。ビームは描画だけでなく、照射線上へ1回の確定ダメージを与えます。
• Trickster（突然変異した Gnome／紫のオーラ）: ミミックです。静かになると、そのへんの財宝そっくりに 化けて待ち伏せします。化けている間はオーラの光さえ消えます。近づく・掴む・攻撃した瞬間、財宝が弾けて ノームが襲いかかってきます。通常の4体組は1グループとして判定され、当選時は4体すべてがTricksterに変異。 1体を倒すとその生涯で1回だけ2体へ分裂し、分裂した子は再分裂しません。実際のリスポーン時に権利が戻ります。
• Big Bang（突然変異した Banger／燃えるオレンジのオーラ）: サイズ2倍、そして設定可能なスカッドで行動。 1体1体がショップのグレネードと同威力で爆発し、その爆発が次の1体を誘爆させ…。
• Glutton（突然変異した Animal／琥珀のオーラ）: お宝を食べます。近くの落ちている財宝を丸呑みし、 食べるたびに硬く・痛く・重く成長。倒せば飲み込んだ財宝を全部その場に吐き出します。
• Alpha（突然変異した Apex Predator／金のオーラ）: 頭上にカウントダウンが出て、0になると変身 — その瞬間 マップ上のランダムな別の敵と位置が入れ替わり、遠吠えでマップ中の敵があなたを狩りに来ます。
• Belladonna（突然変異した Bella／マゼンタのオーラ）: ベルの前兆ごとに周囲の本物のお宝を磁力で周回させ、 標的へ1個ずつ高威力で射出します。バニラより早く攻撃へ移り、一度見つけた相手を長く追い続けます。
• Flambé（突然変異した Chef／燃えるオレンジのオーラ）: 攻撃のたび周囲4方向へ本物の起動済みグレネード をばら撒きます。このグレネードは敵には効かず、プレイヤーだけを吹き飛ばします。
• Fenrir（突然変異した Elsa／氷青のオーラ）: 犬がプレイヤーを見つけると立ち止まり、頭上にカウントダウン が出ます。0になると変身して通常通り襲ってきます。逃げる時間はほんの少し — 撫でても止まりません。 変身時にはダメージのある衝撃波も放つため、近くで待ち構えるのは危険です。
• Redline（突然変異した Reaper／灼熱の赤いオーラ）: 高速追跡中に自分が走った経路を記録し、攻撃へ入ると 赤い軌道を点灯。古い地点から現在地点へ向けて殺傷パルスが追跡経路を再走します。
• Singularity（突然変異した Bowtie／紫外線色のオーラ）: 叫び声が重力井戸へ変化し、プレイヤーと 周囲のお宝を中心へ引き寄せ、お宝を周回軌道へ捕獲します。叫びが終わると、捕獲した実物をプレイヤーへ スリングショット射出します。
• Faultline（突然変異した Headman／溶岩色のオーラ）: メイスを振りかぶるたび、最寄りのプレイヤーへ 向けた三叉の亀裂を床に残します。警告後、3本すべてが数秒間その場に残る危険地帯になります。
• Kaleidoscope（突然変異した Clown／電気的な水色のオーラ）: レーザーの着弾点が床の 3つのプリズム爆破地点へ分裂します。警告リングが消える前に横へ抜けてください。
• House Edge（突然変異した Gambit／カジノゴールドのオーラ）: ルーレットの結果が出るたび、 色別のハウスルールを部屋へ追加します。赤は移動禁止、黄は手持ち品没収、緑は敵の回復・防御、 白は連続打ち上げ、黒はプレイヤー同士の位置シャッフルです。
• Resonance（突然変異した Upscream／共鳴する青いオーラ）: 攻撃で周囲のプレイヤーへ残響マークを付与。 カウント終了前に静止しなければならず、残響が戻る瞬間まで動いていたプレイヤーがダメージを受けます。
• Blood Bank（突然変異した Tick／輸血色の緑のオーラ）: プレイヤーからHPを吸うたび、その一部を 周囲の負傷した敵すべてへ分配し、さらに周囲の敵へ一時的なダメージ耐性を付与します。先に倒さないと、 部屋中の敵が回復しながら硬くなります。
• Railgun（突然変異した Rugrat／帯電した水色のオーラ）: 投げるお宝を、高速かつ高威力の発光弾へ 変えます。明るい軌跡で飛んでくる方向は見えますが、直撃は通常より危険です。
• Blackout（突然変異した Robe／黒に近い紫のオーラ）: 狩りを始めると、周囲の室内灯や持ち運び ライトがほぼ消灯し、暗闇の中でRobe自身の追跡速度も上昇します。落ち着くか離れれば、照明と速度は 元に戻ります。
• Contagion（突然変異した Spewer／毒緑のオーラ）: 吐瀉状態へ入るたび、周囲の落ちているお宝を感染させます。 緑に発光する感染品を掴むと、一度だけ毒性反撃が発生して感染が消えます。
• Necromancer（突然変異した Head Grabber／魂色の紫オーラ）: デスヘッドを奪うと、周囲で姿を晒している 全プレイヤーの魂をその頭へ鎖でつなぎます。遮蔽物に一定時間隠れて鎖を切らないと、ダメージを受け、 手持ちを落とされ、頭のもとへ強制的に引き戻されます。
• Heartbreak（突然変異した Heart Hugger／濃いピンクのオーラ）: 噛みつきの前兆でプレイヤー同士を 2人1組の心臓鎖につなぎます。相方と合流して接触を保てば解除。余った1人は幻の心臓まで走る必要があり、 未解除の鎖は脈動するたびに引き寄せとダメージを与え、最後に破裂します。
• Deathlight（突然変異した Oogly／赤いサーチライトのオーラ）: 敵対スポットライトでプレイヤーの位置を 「撮影」します。遮蔽物で視線を一定時間切れば写真を消せますが、失敗するとダメージとともに発光する 撮影地点へ強制巻き戻しされます。
• Aftershock（突然変異した Shadow Child／電気的な紫のオーラ）: 平手打ちのたび、進行方向の通路を挟む 巨大な影の壁を2枚出現させます。壁が閉じきる前に横へ脱出しないと、最終拍手でダメージを受け、 掴んでいる物を失い、通路外へ吹き飛ばされます。
• Parallax（突然変異した Thin Man／位相色の水色オーラ）: 瞬間移動の出発点と到着点が、一時的な 双方向ポータルになります。プレイヤーだけでなく床のアイテムも反対側から勢いよく射出されるため、 部屋そのものが危険な移動パズルへ変わります。

変異体を掴むと名前が表示されるので、何と対峙しているのか一目で分かります。

仕組み

• スポーン時、バニラ敵が一定確率で突然変異します。確率はレベル×2.5%（1タイプ最大25%・どちらも設定可）。 各変異タイプごとに独立して判定するので、深く潜るほど荒れていきます。
• 表示レベルが**5・10・15…**の階では、対応する有効な敵が全員確定で突然変異します。間隔は設定可能で、 DisabledMutants に書いた変異はこの確定階でも無効のままです。
• 一度突然変異した個体は、レベル中にデスポーン→リスポーンを繰り返しても変異したままです。
• 変異体のHPは設定した基礎倍率（既定2倍）から始まり、クリア済みレベルごとに**+0.05倍**ずつ成長します （既定上限3.5倍）。
• 突然変異の判定は敵個体・変異タイプごとの決定論的な乱数を使い、各クライアントが独立して同じ結果へ 到達するため、判定そのものに通信は不要です。能力イベントは敵が元から持つPhotonViewを利用し、HP・ スポーン・ワールド物理はホストが管理、範囲ダメージはR.E.P.O.の被害者権限方式に合わせ各端末で生成します。
• 爆発はダメージ・ノックバック・効果音のあるしっかりした爆発です。

設定・デバッグ

BepInEx/config/com.matsu.repomutations.cfg

• Mutation / ChancePerLevel（レベル×2.5%）、HealthMultiplier（既定2倍）、 HealthBonusPerLevel（既定+0.05倍/クリア）、MaxHealthMultiplier（既定上限3.5倍）、 GuaranteedSurgeInterval（確定変異階の間隔）、DisabledMutants（無効化する変異名をカンマ区切り）、 オーラ光の範囲/強さ
• バランス改訂2では、元の既定値と一時的な弱体値の両方を、より強い新既定値へ自動移行します。 自分で変更した設定値は保持されます。
• 各変異個体の調整（ダメージ・クールダウン・範囲・ビーム/信管時間・カウントダウン・スカッド数・ Gluttonの成長率・経路再走・軌道物体・残留亀裂・色別ルール・静止判定・感染トラップ・Deathgazeの連射加速・ Fenrirの衝撃波・Blood Bankの回復/耐性・Railgunの投擲・Blackoutの範囲/速度・Necromancerの魂回収・ Heartbreakの心臓鎖・Deathlightの巻き戻し・Aftershockの影拍手・Parallaxのゲートなど）
• デバッグ召喚キー（ホストのみ）: F9 = Boomday Boy、F10 = Poltergeist、F8 = Meltdown Crew、 F7 = Snatcher、F6 = Deathgaze、F5 = Deadeye、F4 = Trickster、F3 = Big Bang、F2 = Fenrir、 F1 = Glutton、F11 = Alpha、F12 = Belladonna、Insert = Flambé、Home = Redline、 Delete = Singularity、PageUp = Faultline、End = Kaleidoscope、PageDown = House Edge、 Pause = Resonance、[ = Blood Bank、] = Railgun、Backslash = Blackout、; = Contagion、 Quote = Necromancer、, = Heartbreak、. = Deathlight、/ = Aftershock、BackQuote = Parallax

バグ報告・要望

不具合や要望があれば、こちらのフォームからお願いします: https://docs.google.com/forms/d/e/1FAIpQLSfl7f-oNiwjXjd7mUkfQoqBIhbJhQhhfV-ZmovjJVQ9orwuYQ/viewform

Changelog

1.1.0

• Strength-only 28-mutant normalization:
  • No mutation was reduced below its original 1.1.0 threat. Mutant health remains 2.0x + 0.05x/level with a 3.5x cap; Big Bang remains 80 damage, Meltdown heads remain 75, Trickster remains 50, Belladonna remains 60, and Glutton keeps its original full growth.
  • Weaker direct specials were raised toward the established high-threat group: Deadeye 40→55, Fenrir 45→60, Redline 42→55, Faultline 32→40, Kaleidoscope 28→40, House Edge 40→55, Resonance 45→55 and Contagion 35→50.
  • Poltergeist now has an 11-metre field, faster throws, stronger gravity and a new 25-damage impact at the end of each inversion. Snatcher now deals 45 on relocation; Alpha's full-map hunt lasts 15 seconds.
  • Physical/support kits were raised rather than reduced: Singularity reaches 10 metres with 8x debris impact, Blood Bank heals up to 25 with 45% resistance, Railgun uses 9x impact, and Blackout expands to 16 metres with 1.75x pursuit speed.
  • The five newest mutants were raised: Necromancer 50, Heartbreak 10-per-pulse/50 snap, Deathlight 50, Aftershock 60 and Parallax 25, alongside stronger range, pull, duration or activation pressure.
  • Balance revision 2 recognizes both original and temporarily lowered defaults and moves them to this stronger preset automatically, while preserving manually customized config values.
• Large mutation rework:
  • Levels 5, 10, 15, ... are now guaranteed mutation surges: every enabled supported enemy mutates. GuaranteedSurgeInterval controls the interval and DisabledMutants remains respected.
  • Trickster now rolls once per vanilla four-Gnome group, so all four mutate together. A killed Trickster splits into two real networked Gnomes once per life; children cannot split again, and a genuine respawn resets the entitlement.
  • Deadeye no longer relies on the Photon Blaster prefab's visual/internal collider. An unobstructed beam now applies one explicit victim-authoritative line hit, so it cannot be visual-only.
  • Poltergeist has stronger default range, lift and throw cadence, plus a periodic high-gravity inversion that slams players and floating objects back down.
  • Belladonna replaces unreliable phantom decoys with cursed cargo: her bell pulls nearby real valuables into orbit and launches them at the target with boosted physical impact damage.
  • Redline (mutated Reaper) — records its overclocked chase route, then sends a lethal moving pulse back through that exact path.
  • Singularity (mutated Bowtie) — captures real valuables in orbit during its gravity-well yell, then slingshots every captured object at players when the yell ends.
  • Faultline (mutated Headman) — every mace attack leaves a persistent three-branch floor fracture; after warning, all branches remain dangerous for several seconds.
  • House Edge (mutated Gambit) — roulette colours now invoke distinct house rules: Red Light, loot confiscation, enemy insurance, player launches, or a position shuffle.
  • Resonance (mutated Upscream) — marks nearby players with a returning echo; players must stop moving before it returns or take explicit damage.
  • Contagion (mutated Spewer) — puke infects nearby loose valuables. Infected loot visibly glows and triggers a one-shot toxic backlash when grabbed.
• Five additional mutants — 28 total:
  • Necromancer (mutated Head Grabber) — a stolen death head soul-chains exposed players; sustained cover severs the chain, while failure disarms and recalls the victim toward the head.
  • Heartbreak (mutated Heart Hugger) — forges paired player chains that require a held reunion to break, with a phantom-heart objective for an unpaired player.
  • Deathlight (mutated Oogly) — photographs players in its hostile spotlight; cover erases the image, while failure rewinds the victim to the captured position.
  • Aftershock (mutated Shadow Child) — each slap closes two giant shadow walls around a corridor; players must escape laterally before the final clap catches, disarms and throws them.
  • Parallax (mutated Thin Man) — every teleport creates temporary two-way gates that transport and launch both players and loose physics objects between the exact endpoints.
• Snatcher keeps its instant safe-map teleport and initial damage, but its delayed destination bomb has been removed.
• Unchanged by request: Boomday Boy, Meltdown Crew, Kaleidoscope, Blood Bank, Railgun and Blackout retain their 1.0.0 abilities and tuning. Other mutations not listed above also keep their existing kits.
• Added tuning sections and host debug keys for Contagion and all five additional mutants.

1.0.0

• Nine brand-new mutants — 22 total:
  • Redline (mutated Reaper) — an overclocked pursuit that leaves explosive wakes along its route.
  • Singularity (mutated Bowtie) — its yell creates a gravity well followed by a final implosion.
  • Faultline (mutated Headman) — mace attacks trigger a telegraphed chain of four floor eruptions.
  • Kaleidoscope (mutated Clown) — its laser impact splits into three delayed floor detonations.
  • House Edge (mutated Gambit) — its roulette creates an explosive clockwise ring.
  • Resonance (mutated Upscream) — attacks leave delayed echoes at players' recent positions.
  • Blood Bank (mutated Tick) — bites convert stolen health into healing pulses for nearby enemies.
  • Railgun (mutated Rugrat) — thrown valuables gain extra speed, impact damage and a projectile trail.
  • Blackout (mutated Robe) — suppresses nearby room and carried lights while hunting.
• Threat escalation pass for five weaker mutants:
  • Snatcher gained an unstable destination rift and 25 initial teleport damage.
  • Deathgaze fires sooner, hits harder and accelerates repeated beams during an uninterrupted stare.
  • Fenrir transforms sooner and releases an enemy-safe shockwave when its countdown reaches zero.
  • Blood Bank also grants nearby enemies temporary damage resistance.
  • Blackout gains a configurable pursuit-speed boost while its darkness field is active.
• Late-run threat scaling: mutant health gains a configurable bonus per completed level and respects a configurable maximum multiplier.
• Added Mutation / DisabledMutants, allowing individual mutations to be disabled without removing the mod.
• Gave each mutation type an independent deterministic roll salt so all clients agree without species sharing equivalent ViewID roll streams.
• Removed obsolete pity-state scaffolding and made per-level sticky mutation state explicit per mutant type.
• Added tuning sections and host debug keys for the nine new mutants, plus the new threat-scaling options.

0.10.0

• Hivemind is gone — meet the Trickster (mutated Gnome). The population-doubling Hivemind could lag the game badly, so the Gnome mutation was redesigned: the Trickster is a MIMIC — it disguises itself as a random valuable and ambushes whoever comes to collect it.
• Five brand-new mutants:
  • Big Bang (mutated Banger) — twice the size, roams in a squad of five, and detonates with the full shop-grenade blast. One going off tends to set off the rest.
  • Glutton (mutated Animal) — swallows any loose valuable it gets close to, and every meal makes it tougher, harder-hitting and heavier (bigger valuables feed it more). Kill it to get your haul back.
  • Alpha (mutated Apex Predator) — freezes with a countdown before transforming; at zero it trades places with a random other enemy on the map, then howls — every enemy hunts its prey for a while. Works for provoked/touched transformations too.
  • Belladonna (mutated Bella) — her bell-ring attack tell summons a swarm of identical phantom decoy tricycles that charge in alongside her. Same look, same sound — the real one hits hardest, but a decoy still costs you. She also escalates to her bell/attack sequence far faster than vanilla and holds a grudge much longer once provoked.
  • Flambé (mutated Chef) — flings four real, armed shop grenades around itself each tumble attack. Its grenades can't hurt enemies — only players.
• New config sections: Trickster, BigBang, Glutton, Alpha, Belladonna, Flambe (the old Hivemind section is gone). New debug spawn keys: F3 / F1 / F11 / F12 / Insert.
• Post-release polish pass: silenced the Trickster's disguise (its own footsteps/idle sounds no longer give it away); fixed Big Bang's squad occasionally summoning far more than its configured size when multiple mutants rolled near each other; fixed the Alpha sometimes showing its post-transform model/animation years before its countdown actually finished; Glutton's growth from eaten valuables now correctly resets when it's actually killed (a mere despawn still preserves it).
• Full self-audit: reviewed every mutation and Harmony patch for host/client desync bugs. Fixed one narrow edge case — a Flambé grenade's fuse time could go out of sync between the host and clients if Flambe/GrenadeFuseSeconds was changed away from its default, causing an occasional client-side double detonation effect. Everything else checked out: mutation rolls are correctly deterministic across every client, all damage/knockback correctly reaches every player, and no other host-only gaps were found.

0.9.3

• Fixed: Boomday Boy balloons not exploding when physically touched/punched. Vanilla's own balloon pop handler (CheckForPoppedBalloons → RemoveBalloon) runs before our distance-based check, silently removing the balloon before the explosion could trigger. Now intercepted via a Harmony Prefix on RemoveBalloon: any Boomday Boy balloon that gets popped also detonates.

0.9.2

• Fixed: Mutation aura/glow only visible on host. The mutation component was attached during EnemyParent.Spawn when Photon ViewID is still 0, causing the deterministic roll to disagree between clients — only the host's copy would mutate. Fixed by switching to SpawnRPC which fires after ViewID is assigned, so all clients always agree.
• Fixed: Deadeye (mutated Huntsman) Photon Blaster beam dealt no damage to non-host players. The beam's HurtCollider was incorrectly disabled on non-host clients. REPO's damage system is victim-authoritative (IsMine check inside HurtCollider.PlayerHurt) — each client must have its own active collider to register damage on its own player. Restored for all clients. Also fixed: beam could stop firing permanently after the first shot (_activeBeam null-check bug).
• Fixed: Boomday Boy explosions (proximity blast, death blast, balloon chain, balloon contact) dealt no damage to non-host players. All four explosion paths now broadcast via [PunRPC] on the enemy's PhotonView so every client spawns the explosion locally. Victim-authoritative HurtCollider prevents double damage automatically.
• Confirmed: Fenrir countdown display runs on every client independently (state is RPC-synced by vanilla EnemyElsa). No fix needed.
• Confirmed: Meltdown Crew 3 heads fully synced — extra heads are Photon network objects (SpawnNetworkPrefab) and their explosions use [PunRPC] ExplodeRPC. No fix needed.
• Stronger mutation auras — default glow intensity 4.5 → 12, light range 3.7 m → 6 m. Adjustable in BepInEx config.

0.9.1

• Fixed mutations happening far too often — enemies could all end up mutated even on early levels, ignoring the configured chance. Mutation odds now work as intended.
• New MaxChance cap (default 25% per enemy type) so the per-level scaling can't run away to a near-guaranteed mutation on deep runs. Raise it to 1 for the old behaviour, or lower it to make mutants rarer.

0.9.0

• Three new mutants:
  • Deadeye (mutated Huntsman) — shoots the players' own Photon Blaster: a sustained laser beam.
  • Hivemind (mutated Gnome) — multiplies over time. One gnome becomes two, becomes four...
  • Fenrir (mutated Elsa) — the dog freezes and a countdown appears over its head when it spots you; when it hits zero it transforms and hunts as normal. Just enough time to run. Petting won't save you.
• Mutants now show their name when you grab one (e.g. "Fenrir", "Boomday Boy").
• Mutation chance reworked: now a flat 2.5% per level with no upper cap (was 1% + a pity system), so deeper runs get much wilder.
• Brighter auras — mutants now glow more strongly so they're easier to spot.
• Fix: Deathgaze's beam no longer gets blocked when the Peeper is mounted on the ceiling.

0.8.0

• Auras are now actually visible — the coloured mutation aura is a proper light now, so you can spot a mutant at a glance (even the otherwise-invisible Snatcher).
• Meltdown Crew now lobs three heads at once (normal / sluggish / frantic speed) instead of one at a time — fully synced for everyone.
• Poltergeist — its zero-gravity field range is now shown, its thrown objects hurt players properly again, and it no longer damages/stuns itself with its own throws. Field range trimmed a little.
• Boomday Boy — its blasts deal damage again, no longer knock/hurt itself, and it turns hostile and chases you after it goes off.
• Deathgaze stare time increased a bit, and its beam no longer gets blocked by the Peeper itself.

0.7.0

• New mutant: Deathgaze (mutated Peeper). Don't let it hold you in its stare for too long.

0.6.0

• Two new mutants:
  • Meltdown Crew (mutated Cleanup Crew, toxic-green aura): instead of lobbing one bomb-head, it fires a 3-shot volley — normal speed, then a sluggish half-speed head, then a frantic double-speed head.
  • Snatcher (mutated Hidden, violet aura): instead of slowly dragging a grabbed player far away on foot, it instantly teleports them to a random spot on the map (verified to be solid ground, never a pit) and hurts them the moment it grabs.
• Mutation chance reworked into a pity system: chance is now level% + pity, where pity grows by that level's own level% for every level a given mutation type fails to appear, and resets to 0 the moment it does — so a long dry streak makes the next appearance increasingly likely, independently per mutant type.
• Sticky per-individual mutation: once a specific enemy mutates, it stays mutated through every despawn/respawn cycle within the same level (previously it could theoretically re-roll). Verified this also works correctly with two enemies of the same type alive at once, one mutated and one not.
• New jacket artwork.

0.5.0

• Everyone must install: mutation attachment now happens independently on every client (a deterministic per-enemy roll), so mutation auras and visuals render correctly for all players, not just the host.
• Mutation auras recolored: replaced the point-light aura with a Fresnel rim-glow on the enemy's own model (Boomday Boy = orange, Poltergeist = light blue), visible to every client.
• Real explosions: Boomday Boy's blasts now use the game's actual explosion (damage, knockback, and sound), replacing the old fixed-damage/VFX-only approach.
• Balloon rules overhauled:
  • A player touching a balloon now explodes only that single balloon — no more chain reaction on touch.
  • An enemy touching a balloon just pops it harmlessly.
  • Death/recurring-blast chain reactions now detonate balloons in the order they were placed, one every 0.1 seconds, and this fix also makes the touch-explosion actually trigger reliably.
  • Multiple Boomday Boys now correctly track only their own balloons.
• Slightly reduced Boomday Boy's explosion damage.
• Poltergeist rework: removed the indiscriminate telekinetic damage entirely. Thrown valuables now use the same throw physics as the game's own loot-throwing enemy — the object's own impact deals the damage, so there's no more artificial or unavoidable hit.
• Mutant health multiplier (2x by default) now reliably applies to the enemy's current health, not just its maximum.

0.4.2

• Rebalanced Boomday Boy explosion damage and mutation chance scaling (level x 1% by default).

0.4.0

• Added Poltergeist (mutated Mentalist): persistent zero-G field + telekinetic barrage.

0.1.0

• Initial release. Boomday Boy (mutated Birthday Boy): recurring bomber with chain-exploding balloons.