Signal Pest [Wizards Play Network 2011] Oath of the Gatewatch Prerelease Promos each creature you control with

each creature you control with power 4 or greater gets +1/+1 and gains trample until end of turn

At the beginning of the next end step

Serra Ascendant gets +5/+5 and has flying

Numsgil did in Blog

Signal Pest [Wizards Play Network 2011] Oath of the Gatewatch Prerelease Promos each creature you control withSet: Wizards Play Network 2011 Type: Artifact Creature Pest Rarity: Rare Cost: {1} Battle cry (Whenever this creature attacks, each other attacking creature gets +1 +0 until end of turn.) Signal Pest can't be blocked except by creatures with flying or reach. It leaps from tree to tree, revealing the enemy's positions.