P Fury of the Xer'Sai
Passive
Innate: Rek'Sai basic attacks generate 25 Fury on-hit, reduced to 4 per hit against minions, and to 5 per hit against wards and jungle plants. Rek'Sai's abilities other than Queen's Wrath generate 25 Fury upon hitting at least one unit. Prey Seeker does not generate Fury against non-champions hit. After 8 seconds of being out of combat, she loses 20 Fury per second.
When Rek'Sai becomes Burrowed, she consumes her current Fury over 3 seconds to heal for 0% – 100% (based on Fury) of 9% – 21.29% (based on level) maximum health, stopping once fully consumed or she reaches full health. If she starts generating Fury while Burrowed, the consumption occurs after 5 seconds.