King of Tokyo is what happens when Richard Garfield (Magic: The Gathering, RoboRally) decides to design a family game. The dice mechanic is pure Yahtzee — roll six, keep some, reroll twice more — but the symbols on the dice trigger different actions.
The central tension is the Tokyo rule. The monster occupying Tokyo can't heal and takes damage from every other player's attacks, but their attacks hit EVERYONE outside Tokyo. Going into Tokyo is high-risk, high-reward.
The game peaks at 4-5 players where the inside-Tokyo monster is fighting 3-4 outside attackers. Two-player is significantly weaker.