This module is a fork of foundryvtt-retroactive-advantage-5e by Andrew Krigline (ElfFriend-DnD), later maintained by Zhell (krbz999). Huge thanks to both for their foundational work — this module would not exist without them.

This module allows a user to retroactively change a d20 roll's advantage status directly from the chat card, without affecting any other module logic based on the original roll.

• Adds Advantage, Normal, and Disadvantage buttons to any d20 roll chat card
• The current mode is highlighted (disabled button), making the active state immediately clear
• As much as possible, previously rolled dice are reused — only a new die is rolled when strictly necessary (e.g., moving from Normal to Advantage)
• Works with standard attack rolls, ability checks, saving throws, and any other d20 rolls handled by the dnd5e system
• Hover-only mode (optional): buttons can be configured to appear only when hovering over a message, reducing visual clutter

• ✅ Halfling Luck
• ✅ Reliable Talent
• ✅ Elven Accuracy (requires actor to have the trait and the roll to use DEX/INT/WIS/CHA)

The following changes have been made in this fork relative to the krbz999 maintained version:

• Updated the module manifest (module.json) to declare compatibility with Foundry VTT V13 and V14 ("minimum": "13", "verified": "14")
• Uses the modern dnd5e.renderChatMessage hook (introduced in dnd5e 3.x+), which is the correct V13/V14 lifecycle hook for injecting chat card UI
• Replaced legacy advantage modifier injection with a call to configureModifiers() on the new D20Roll instance, deferring advantage/disadvantage setup entirely to the system. A safe fallback is still included for older system versions

• Cleaner base formula generation: The d20 term is now reconstructed as a pristine 1d20 before re-applying system modifiers, preventing stale kh/kl modifiers from accumulating across repeated button presses
• Backup roll management: The module intelligently decides what to save as the backup roll — if the new roll has more dice than the original (e.g., adding a second d20 for advantage), the richer roll is saved as the backup to preserve all results for future mode switches
• Correct dice result restoration: Historic die results are restored from the baseline roll, and modifier re-evaluation (_evaluateModifiers()) is called to correctly activate/discard dice according to the new mode

• Retroactive advantage now fully supports Elven Accuracy — when switching to Advantage, the module checks whether the roll's actor has the trait enabled (actor.system.traits.elvenAccuracy) and whether the roll targets an eligible ability (DEX, INT, WIS, or CHA)
• When EA applies, configureModifiers() is called with elvenAccuracy: true, which causes the dnd5e system to natively apply the adv2 modifier — rolling 3d20kh1 instead of 2d20kh1
• If the original roll was already flagged with elvenAccuracy: true (i.e. it was an EA roll from the start), that flag is honoured directly without re-checking the actor
• When switching away from an EA advantage roll (e.g. to Disadvantage or Normal), the 3-die result set is trimmed to the correct count (2 for dis/adv, 1 for normal) before modifier re-evaluation, preventing incorrect totals
• If the actor cannot be resolved from the message speaker (e.g. unlinked token, no speaker), EA detection gracefully falls back to false and normal advantage is applied instead

• When a new die needs to be rolled (e.g., upgrading a Normal roll to Advantage), Dice So Nice is invoked to animate only the newly introduced die — not the full roll — for a natural visual result
• The DSN filter correctly handles EA rolls: when 2 new dice are rolled (Normal → EA advantage), both are animated; when 1 new die is added (Advantage → EA advantage), only that die animates

• Added a per-user module setting (showOnHover) that, when enabled, applies a hover-only CSS class to the button menu
• The CSS smoothly transitions buttons in and out using opacity and max-height with a 0.15s ease transition, avoiding layout jumps

• Button styling uses dnd5e design tokens (--dnd5e-color-hd-1, --dnd5e-color-hd-2) for the active/disabled state, blending naturally with the system's UI
• Buttons use nested CSS (modern syntax) for clean, maintainable styling
• The button menu correctly inserts inside .dnd5e2.chat-card containers (system chat cards), with a fallback insertion before .dice-roll for other d20 roll messages

This module is released under the MIT License, in accordance with the original module's licensing terms.

Original copyright © 2022 Andrew Krigline (ElfFriend-DnD). See LICENSE for the full license text.

• Original author: Andrew Krigline (ElfFriend-DnD) — creator of the original module
• Previous maintainer: Zhell (krbz999) — maintained the module through V11/V12 with significant refactors
• This fork: Nik (nschoenwald) — V13/V14 compatibility, UI improvements, and ongoing maintenance