Ghirapur Guide
Creature — Elf Scout
: Target creature you control can't be blocked by creatures with power 2 or less this turn.
Fairgoers were delighted to find that even outside the fairgrounds, Ghirapur was a city of wonders.
Scott Murphy
Jumpstart (JMP)
• #400Rulings
Once a creature with power 2 or less has blocked a creature, activating Ghirapur Guide's ability won't change or undo that block.
(wotc • 2018-07-13)
Once a creature with power 3 or greater has blocked the target creature, changing the power of the blocking creature won't change or undo that block.
(wotc • 2018-07-13)
Rulings
Once a creature with power 2 or less has blocked a creature, activating Ghirapur Guide's ability won't change or undo that block.
(wotc • 2018-07-13)
Once a creature with power 3 or greater has blocked the target creature, changing the power of the blocking creature won't change or undo that block.
(wotc • 2018-07-13)