Kor Bladewhirl

Rally — Whenever Kor Bladewhirl or another Ally you control enters, creatures you control gain first strike until end of turn.

Firemantle Mage

Rally — Whenever Firemantle Mage or another Ally you control enters, creatures you control gain menace until end of turn. (A creature with menace can't be blocked except by two or more creatures.)

Plains

Lantern Scout

Rally — Whenever Lantern Scout or another Ally you control enters, creatures you control gain lifelink until end of turn.

Resolute Blademaster

Rally — Whenever Resolute Blademaster or another Ally you control enters, creatures you control gain double strike until end of turn.

Expedition Envoy

Gideon, Ally of Zendikar

+1: Until end of turn, Gideon, Ally of Zendikar becomes a 5/5 Human Soldier Ally creature with indestructible that's still a planeswalker. Prevent all damage that would be dealt to him this turn.
0: Create a 2/2 white Knight Ally creature token.
−4: You get an emblem with "Creatures you control get +1/+1."

Angelic Gift

Enchant creature
When Angelic Gift enters, draw a card.
Enchanted creature has flying.

Goblin War Paint

Enchant creature
Enchanted creature gets +2/+2 and has haste.

Hada Freeblade

Whenever Hada Freeblade or another Ally you control enters, you may put a +1/+1 counter on Hada Freeblade.

Hero of Goma Fada

Rally — Whenever Hero of Goma Fada or another Ally you control enters, creatures you control gain indestructible until end of turn.

Rally the Ranks

As Rally the Ranks enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.

Kazandu Blademaster

First strike, vigilance
Whenever Kazandu Blademaster or another Ally you control enters, you may put a +1/+1 counter on Kazandu Blademaster.

Retreat to Valakut

Landfall — Whenever a land you control enters, choose one —
• Target creature gets +2/+0 until end of turn.
• Target creature can't block this turn.