IXA: Dinosaur Stampede, Instant 2R Attacking creatures get +2/+0 until end of turn. Dinosaurs you control gain trample until end of turn.

Dinosaur Stampede

Attacking creatures get +2/+0 until end of turn. Dinosaurs you control gain trample until end of turn.

9/29/2017 In a Two-Headed Giant game, attacking creatures your teammate controls get +2/+0, but only Dinosaurs you control gain trample.