010-ability-checks-saves.md

10. Ability Checks & Saving Throws

Date: 2025-11-22

Status

Accepted

Context

The system needs a way to resolve uncertain outcomes (Ability Checks) and resist negative effects (Saving Throws), core mechanics of the d20 system.

Decision

We implemented RollCheck and RollSave methods on the ICheckManager interface (and StandardCheckManager implementation).

• Ability Checks: RollCheck(Ability ability, int dc) rolls a d20 + Ability Modifier + Proficiency (if applicable, though skill proficiency is not yet fully implemented).
• Saving Throws: RollSave(Ability ability, int dc) rolls a d20 + Ability Modifier + Proficiency (if proficient in that save).
• Result: Returns a Result<bool> indicating success or failure against the Difficulty Class (DC).

Consequences

• Creatures can now perform basic d20 tests.
• Foundation laid for Skill Checks (which will wrap RollCheck).
• ICheckManager encapsulates the dice rolling logic for these tests, keeping ICreature cleaner.