> For the complete documentation index, see [llms.txt](https://docs.playhattori.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.playhattori.io/game-info/game-systems/battle/mechanics.md). # Mechanics Combat is a first-person 3D duel aiming to reduce the opponent’s health points (HP) to zero with shuriken throws.
## **Hits** When a player hits a target, the affected body part glows red, kicking off an injury countdown. A sound plays, and damage numbers appear from the HP bar. Critical hits or headshots trigger unique visual effects. ## **Fatigue** Fatigue begins at zero and climbs with each shuriken throw. At its max, a 2-second cooldown blocks further throws. If the player pauses throwing, fatigue drops after a 1-second recovery. The number of throws before max fatigue depends on the weapon’s stats. ## **Shield** Players activate a shield by holding a finger at the screen’s center, absorbing 90% of incoming damage. The shield fails when its capacity hits zero, and throws are disabled during use. Capacity regenerates over time, and the shield activates when hitting the player’s collider. ## **Movement** Players face each other directly, moving via a “pizza” system of point-to-point shifts. They can move left or right from the center by swiping or tapping an indicator, up to a max distance of one ray, if a point is available. Movement also adds fatigue.