Overrun
Sorcery
Creatures you control get +3/+3 and gain trample until end of turn. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Carl Critchlow
Magic 2012 (M12)
• #186Rulings
Overrun affects only creatures you control at the time it resolves. It won't affect creatures that come under your control later in the turn.
(wotc • 2009-10-01)
Rulings
Overrun affects only creatures you control at the time it resolves. It won't affect creatures that come under your control later in the turn.
(wotc • 2009-10-01)