Monkey King vs Undying

How this matchup plays

Seeing an Undying on the other team makes picking Monkey King a really tough call. Monkey King relies on building up Jingu Mastery stacks by staying on a target, but Undying’s Decay saps his strength and health, making it hard to trade hits effectively. Even worse is the interaction with Wukong's Command. A well-placed Tombstone inside Monkey King's ultimate completely neutralizes it. The zombies that spawn will swarm and slow him, often killing him inside his own spell, while the soldiers from his ultimate waste their attacks trying to destroy the tomb itself.

This dynamic starts in the lane, where constant Decay spam makes it nearly impossible for Monkey King to farm or fight. As the game goes on, he can't initiate with his ultimate because he knows Undying is waiting to drop Tombstone. This forces Monkey King to wait for Tombstone to be used on someone else, which a good Undying will rarely do. Monkey King is then relegated to the sidelines, unable to commit to the big teamfights he's designed for, while Undying controls the pace simply by existing.