Powers & Abilities — A complete ability system with five activation types (Instant, Toggle, Hold, Charged, Passive), groupable into Powers with configurable unlock conditions. Includes a drag-and-drop ability inventory, a 6-slot HUD bar with paging, and customizable categories.
Stamina & Overuse — A universal stamina resource that drains when abilities are used and regenerates over time. Pushing too far triggers the Overuse system — a three-stage penalty that discourages ability spam while creating meaningful risk-reward decisions.
Composition — A permanent growth stat unique to each player. Composition increases through gameplay (ability usage, stamina recovery, overuse survival) and directly expands the player's stamina capacity. Diminishing returns ensure no hard cap while maintaining balance.
Power Leveling — Optional per-power XP and leveling. Abilities can require minimum power levels to unlock, and XP is earned through ability usage within that power.
Custom Meters — A flexible value system for addon developers to create their own resources (mana, rage, focus, etc.) with independent drain, regen, and scaling.
Transformations — A dedicated ability type for shapeshifting, with phase transitions, visual data hooks, and automatic inventory management.
Tag System — A lightweight labeling system for gating abilities behind conditions. Tags can be granted by items, events, curios, or any custom logic.
Optional Compatibility — First-class integration with [GeckoLib 4](https://modrinth.com/mod/geckolib), [Curios API](https://modrinth.com/mod/curios), and [Pehkui](https://modrinth.com/mod/pehkui). All optional — Somnium works without any of them.
