Louie, Roar of the World

Eminence — At the beginning of combat on
your turn, if Louie, Roar of the World is
in the command zone or on the battlefield,
another target Cat you control gets +3/+3
until end of turn.
Whenever another Cat you control attacks,
you may pay {1}{g}{w}, if you do, it gains trample
and +X/+X until end of turn, where X is
its power.