Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Agent Frank Horrigan has
indestructible (Effects that say "destroy" don't destroy that permanent. An indestructible creature can't be destroyed by damage.) as long as it attacked this turn.
Whenever Agent Frank Horrigan enters the battlefield or attacks,
proliferate (Choose any number of permanents and/or players, then give each another counter of each kind already there.) twice.