Lucian, Ambitious King

Eminence —Whenever a legendary creature enters
the battlefield under your control, if Lucian is in
the command zone or on the battlefield, you may
pay {2}. If you do, put a champion counter on
that creature then remove all champion counters
from all other creatures you control. As long as
that creature has a champion counter on it, it's
one of your commanders and combat damage it
deals to players is treated as dealt by Lucian.
"My champion will meet you on the field."