Effect: When you win a battle against your opponent's critical move (the Rock-Paper-Scissors sign of their dinosaur), a trio of Velociraptor come and block them from using one of their move buttons during the next battle. In the anime, they stop your opponent from using their Move Cards.
Both the Critical Block and Final Fury arcade cards each have artworks that display the Velociraptor attacking the opponent and standing beside the dinosaur using the Move. The only way to distinguish the two Moves is by comparing the Japanese names: Final Fury has 4 characters in its name; Critical Block has 5 characters in its name, the last of which looks like a backwards capital "J" with a double-quote mark in the top-right gap (this: じ).
In the anime, Critical Block and Final Fury are part of the same triangular "Multiple Move" Card created by Seth.
In the arcade, no damage is dealt by the Velociraptors themselves when Critical Block is activated, despite having the same animation as the damage-dealing Final Fury.