Arms Race

{3}{R}: You may put an artifact card from your hand onto the battlefield. That artifact gains haste. Sacrifice it at the beginning of the next end step.

Champion of Rhonas

You may exert Champion of Rhonas as it attacks. When you do, you may put a creature card from your hand onto the battlefield. (An exerted creature won't untap during your next untap step.)

Belbe's Portal

As Belbe's Portal enters, choose a creature type.
{3}, {T}: You may put a creature card of the chosen type from your hand onto the battlefield.

Aetherplasm

Whenever Aetherplasm blocks a creature, you may return Aetherplasm to its owner's hand. If you do, you may put a creature card from your hand onto the battlefield blocking that creature.