Stella, The Biggest Baby

Eminence - At the beginning of combat
on your turn, if Arahbo, 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 gets +X/+X
until end of turn, where X
is its power.