Zendikar Rising

Canyon Jerboa | Creature | Mouse | Landfall — Whenever a land enters the battlefield under your control, creatures you control get +1/+1 until end of turn. | Antonio José Manzanedo

Allied Assault | Instant | | Up to two target creatures each get +X/+X until end of turn, where X is the number of creatures in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.) | Josh Hass

Paired Tactician | Creature | Human Warrior | Whenever Paired Tactician and at least one other Warrior attack, put a +1/+1 counter on Paired Tactician. | Colin Boyer

Kargan Warleader | Creature | Human Warrior | Other Warriors you control get +1/+1. | Colin Boyer