Roil Spout (BFZ)

Sorcery

Put target creature on top of its owner's library. Awaken 4—{4}{W}{U} (If you cast this spell for {4}{W}{U}, also put four +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Niche creature bounce for control and tempo strategies, but the effect is narrow and the mana cost is steep compared to efficient alternatives like Swords to Plowshares or Counterspell. The awaken clause offers a land-based win condition in Commander, but requires significant mana investment and telegraphs your plan several turns in advance.

Battle for Zendikar — Uncommon