---
key: mechanic/boss-fight-atlas--boss-ally-theft
type: mechanic
id: boss-fight-atlas--boss-ally-theft
lang: en
title: Ally theft and charm
summary: An existing ally temporarily changes allegiance and becomes a threat.
updatedAt: '2026-10-22'
status: active
url: >-
https://gamemechanics.pro/en/knowledge/mechanic/boss-fight-atlas--boss-ally-theft/
jsonUrl: >-
https://gamemechanics.pro/api/v1/knowledge/en/mechanic/boss-fight-atlas--boss-ally-theft.json
markdownUrl: >-
https://gamemechanics.pro/content/knowledge/en/mechanic/boss-fight-atlas--boss-ally-theft.md
aliases: []
tags:
- Boss fights
- 'States, resources, and scaling'
sourceIds:
- source-5387d37f98d2db0d
- source-3be68a97d1aeadb2
- source-89352613766e5833
- source-bca6cf62c24cfbf4
- source-c0f2aaf036deec28
- source-c151324fe6097460
- source-d57ce0c85fd553f3
- source-4330310a4b30fdb4
- source-2c413a292b57f033
- source-baa603af3b0bf305
sources:
- id: source-5387d37f98d2db0d
title: 'Boss Fight Atlas: Ally theft and charm (RU)'
url: 'https://polyakovin.github.io/boss-fight-atlas/ru/mechanics/ally-theft/'
verifiedAt: null
- id: source-3be68a97d1aeadb2
title: 'Boss Fight Atlas: Ally theft and charm (EN)'
url: 'https://polyakovin.github.io/boss-fight-atlas/en/mechanics/ally-theft/'
verifiedAt: null
- id: source-89352613766e5833
title: 'The Siren · The Binding of Isaac: Repentance'
url: 'https://www.youtube.com/watch?v=qj288Dmw8Q0&t=5s'
verifiedAt: null
- id: source-bca6cf62c24cfbf4
title: Fiore DeRosa · Bravely Default
url: 'https://www.youtube.com/watch?v=vMRukz57fnc&t=330s'
verifiedAt: null
- id: source-c0f2aaf036deec28
title: 'Lady Deathwhisper · World of Warcraft: Wrath of the Lich King'
url: 'https://www.youtube.com/watch?v=mseB_We9mes&t=40s'
verifiedAt: null
- id: source-c151324fe6097460
title: 'Boss Up: Boss Battle Design'
url: 'https://media.gdcvault.com/gdc2018/presentations/Keren_Itay_BossUp.pdf'
verifiedAt: null
- id: source-d57ce0c85fd553f3
title: The Siren — The Binding of Isaac Wiki
url: 'https://bindingofisaacrebirth.wiki.gg/wiki/The_Siren'
verifiedAt: null
- id: source-4330310a4b30fdb4
title: 'Bravely Default: Chapter 2 — StrategyWiki'
url: 'https://strategywiki.org/wiki/Bravely_Default/Chapter_2'
verifiedAt: null
- id: source-2c413a292b57f033
title: Lady Deathwhisper — Warcraft Wiki
url: 'https://warcraft.wiki.gg/wiki/Lady_Deathwhisper'
verifiedAt: null
- id: source-baa603af3b0bf305
title: 'The Binding of Isaac: Repentance'
url: 'https://www.youtube.com/watch?v=qj288Dmw8Q0&t=30s'
verifiedAt: null
relations: []
placements:
- catalogId: boss-fight-atlas
id: boss-ally-theft
title: Boss fights
url: 'https://gamemechanics.pro/en/mechanics/boss-fight-atlas/#boss-ally-theft'
categoryIds:
- catalog-part-12
supersededBy: []
attributes:
preview:
updatedAt: '2026-10-22'
title: Ally theft and charm
description: An existing ally temporarily changes allegiance and becomes a threat.
image:
src: images/mechanics/boss-final-qj288dmw8q0-30.webp
width: 640
height: 360
game: 'The Binding of Isaac: Repentance'
sourceUrl: 'https://www.youtube.com/watch?v=qj288Dmw8Q0&t=30s'
originalUrl: 'https://www.youtube.com/watch?v=qj288Dmw8Q0'
sourceFrameSeconds: 30
credit: Nicalis / Edmund McMillen; gameplay capture by SlayXc2
rights: >-
Game graphics © Nicalis / Edmund McMillen. Gameplay recording by
SlayXc2. Original visible source markings retained. All rights reserved;
excluded from portal MIT and CC BY 4.0.
caption: 'The Binding of Isaac: The Siren’s song can charm familiars'
alt: 'The Binding of Isaac: The Siren’s song can charm familiars'
markers:
- x: 57
'y': 23
label: The song temporarily turns an existing familiar to The Siren’s side
tips:
- >-
Show the ally’s allegiance change and a clear moment of returning to
player control.
examples:
- title: 'The Binding of Isaac: Repentance'
url: 'https://www.youtube.com/watch?v=qj288Dmw8Q0&t=30s'
endsAt: null
provenance: >-
Editorial reference index based on the 124 public Boss Fight Atlas mechanic
pages checked on 2026-10-20. Original concise RU/EN definitions by
gamemechanics.pro; source categories, game/boss associations and reference
URLs retained from the atlas. Linked materials retain their original rights;
references are upstream attributions, not independent verification.
license: CC-BY-4.0
codeLicense: MIT
attribution: gamemechanics.pro contributors
catalogKey: catalog/boss-fight-atlas
---
# Ally theft and charm
id: boss-fight-atlas--boss-ally-theft
type: mechanic
key: mechanic/boss-fight-atlas--boss-ally-theft
lang: en
status: active
url: https://gamemechanics.pro/en/knowledge/mechanic/boss-fight-atlas--boss-ally-theft/
An existing ally temporarily changes allegiance and becomes a threat.
## At a glance
[The Binding of Isaac: Repentance](https://www.youtube.com/watch?v=qj288Dmw8Q0&t=30s) · Game graphics © Nicalis / Edmund McMillen. Gameplay recording by SlayXc2. Original visible source markings retained. All rights reserved; excluded from portal MIT and CC BY 4.0.
[Source recording](https://www.youtube.com/watch?v=qj288Dmw8Q0), 30 s
1. The song temporarily turns an existing familiar to The Siren’s side
- Show the ally’s allegiance change and a clear moment of returning to player control.
- [The Binding of Isaac: Repentance](https://www.youtube.com/watch?v=qj288Dmw8Q0&t=30s)
## How it works
An existing ally temporarily changes allegiance and becomes a threat.
## Variants
### How the technique works
- An existing ally temporarily changes allegiance and becomes a threat.
## Context and limits
A concise reference to all 124 Boss Fight Atlas mechanics across its 14 source sections. Each entry includes a definition, full RU/EN lesson links, game references and further reading retained from the source. Animations and detailed rules remain in the atlas.
## Connected materials
## Sources and provenance
Editorial reference index based on the 124 public Boss Fight Atlas mechanic pages checked on 2026-10-20. Original concise RU/EN definitions by gamemechanics.pro; source categories, game/boss associations and reference URLs retained from the atlas. Linked materials retain their original rights; references are upstream attributions, not independent verification.
- [Boss Fight Atlas: Ally theft and charm (RU)](https://polyakovin.github.io/boss-fight-atlas/ru/mechanics/ally-theft/) (id: source-5387d37f98d2db0d)
- [Boss Fight Atlas: Ally theft and charm (EN)](https://polyakovin.github.io/boss-fight-atlas/en/mechanics/ally-theft/) (id: source-3be68a97d1aeadb2)
- [The Siren · The Binding of Isaac: Repentance](https://www.youtube.com/watch?v=qj288Dmw8Q0&t=5s) (id: source-89352613766e5833)
- [Fiore DeRosa · Bravely Default](https://www.youtube.com/watch?v=vMRukz57fnc&t=330s) (id: source-bca6cf62c24cfbf4)
- [Lady Deathwhisper · World of Warcraft: Wrath of the Lich King](https://www.youtube.com/watch?v=mseB_We9mes&t=40s) (id: source-c0f2aaf036deec28)
- [Boss Up: Boss Battle Design](https://media.gdcvault.com/gdc2018/presentations/Keren_Itay_BossUp.pdf) (id: source-c151324fe6097460)
- [The Siren — The Binding of Isaac Wiki](https://bindingofisaacrebirth.wiki.gg/wiki/The_Siren) (id: source-d57ce0c85fd553f3)
- [Bravely Default: Chapter 2 — StrategyWiki](https://strategywiki.org/wiki/Bravely_Default/Chapter_2) (id: source-4330310a4b30fdb4)
- [Lady Deathwhisper — Warcraft Wiki](https://warcraft.wiki.gg/wiki/Lady_Deathwhisper) (id: source-2c413a292b57f033)
- [The Binding of Isaac: Repentance](https://www.youtube.com/watch?v=qj288Dmw8Q0&t=30s) (id: source-baa603af3b0bf305)
CC-BY-4.0 · gamemechanics.pro contributors