From StrategyWiki, the free strategy guide and walkthrough wiki

[edit] Game Display

Player Health Bar - Located in the bottom left corner of the screen. It starts at 100 and will be reduced when you take damage. Once it reaches 0 you are dead and will have to restart your mission. Enemy Health Bars - Will appear at the top of the screen every time you engage an enemy in combat. Attack the enemy to reduce their health bar to 0 and kill them. Inventory - The bottom right corner of the screen displays all your available items in a row, and the quantity of each. The selected item is highlighted with a yellow cursor.

[edit] Ki Meter

The Ki Meter is a representation of your ability to sense the presence and awareness of others. It is an essential tool for remaining undetected, knowing when to go in for the kill, and when to flee the area.

The Ki Meter will shrink and grow and be accompanied by a number (0-100) depending on how far away you are from another character. The larger the number, the closer you are to an enemy. The Ki Meter will also change symbols, to indicate the awareness of the enemy.

	Enemy is completely unaware of your presence, and will continue on it's patrol path as normal. You may perform a Stealth Kill, or move on undetected.
	Enemy is aware of your presence, but is unsure if you are a friend or a threat. Enemy will come closer to examine the situation. It is best to hide or get some distance to avoid being spotted.
	Enemy has found a dead body or has been alerted to your presence, and is actively seeking you out. Stay hidden, and wait for them to give up. They should return to their normal patrol after a while.
	You have been spotted! Enemy will immediately pursue and attack you with the intent of taking your life. Evade the enemy or fight back.