HP5 (also known as HP/5) is a shortened term for the item bonus "Restores X health per 5 sec." Although the number given is based on 5 second intervals, the effect will trigger every 2 seconds. For example, an item that grants 10 health per 5 sec will restore 4 health on every "tick". Health regeneration depends on Spirit and HP5 bonuses, in most cases Spirit only affects regen outside of the 5 second rule, while HP5 bonuses apply at all times.
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