Generates a Ferocity stack on casting an auto-attack. On reaching 4 stacks, his next basic ability will be empowered, which will grant an additional cast of this ability along with bonus Movement Speed for 1.5 seconds. It will also empower some of your abilities but will consume all the Ferocity stacks. The stacks are lost if Rengar is out of combat for 8 seconds.
When hiding in a brush, Rengar's auto-attacks gain a pounce range. On attacking a target, he will leap to that target and attack them. This effect lasts for 0.25 even after leaving a brush but is lost immediately if he casts Flash. Leaping with no Ferocity stacks generates 1 Ferocity stack.
Bonetooth Necklace: Taking down an enemy within 1.5 seconds of damaging them will grant you a trophy per unique champion, up to 5. These trophies grant bonus AD per stack.