Scott, Heartsworn Protector

First Strike.

When Scott, Heartsworn Protector enters the battlefield, choose a creature you control. That creature gains lifelink and gets +X/+X until end of turn, where X is the number of creatures you control that have first strike or lifelink.
Whenever a creature you control with first strike or lifelink deals combat damage, Scott Heartsworn Protector deals that much damage to any target.

"In love, loyalty is both shield and sword."