Card name: Coralhelm Guide
Mana Cost: CMC1Color U
Converted Mana Cost: 2
Types: Creature — Merfolk Scout Ally
Card Text: CMC4Color U: Target creature can't be blocked this turn.
Flavor Text: "She knows every step of this coastline, both above and below the surface, and she has hideouts all along the way. She will get you there."—Jori En, expedition leader
P/T: (2/1)
Expansion: BFZC Battle for Zendikar
Rarity: Common

Coralhelm Guide
Card rulings (?)
2015-08-25 Once an attacking creature has been legally blocked, making it so it can't be blocked won't change or undo that block.