Hooked Claws (4e Feat)
From D&D Wiki
+2 to all attack rolls that include Grab as a part of the attack and Athletics checks, and enemies take your Dexterity modifier in damage when you successfully Grab them.
Prerequisite: Sentient, Smilodon Maioribus
Benefit: Your titanic paws are naturally armed with flesh rending claws, and you've now mastered their flesh hooking capability; you gain a +2 bonus to all attack rolls that include Grab, in addition to Athletics checks, and enemies you successfully Grab take your Dexterity modifier in damage instantly as bonus damage.