A stage spike is a resulting action from knocking an opponent into a wall or other solid object, where, if they don't perform a Ukemi immediately, they will be knocked away from the object. This will often result in a knock-out if done against the side of a stage such as Yoshi's Island, and is a useful thing to employ with characters who have no true meteor smash of their own.
Recovering tether characters who are being edge-hogged will also have the capability to stage-spike an opponent who does not use invulnerability frames properly.
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