A crush is a very uncommon method of being KOed, which involves the player's character being stuck between two solid platforms that move into each other; if the player is unable to move out of the way from the common collision point of the two platforms, then they will be crushed when the two platforms meet. This results in an instant KO, without passing the blast line and without regards to the player's accumulated damage.
Stages that can crush
On Pirate Ship, players can be crushed when the ship crashes onto the rocky island. If players jump off the ship onto the rightmost edge of the island just before the ship can actually crash into it, then they will be crushed by the collision between the island and the ship. This crush, however, is difficult to perform, as touching the hull of the ship before the collision will result in getting meteor smashed instead. While the stage returned in the Wii U version of Smash 4 as a DLC stage, the crush was removed; instead, players are spiked by the ship and ricochet off the island, resulting in a KO across the upper blast line.
In Midgar, summoning Odin via Summon Materia on the stage will cause him to slice the stage in half. After some time, the two halves of the stage will come back together; players caught in between these two halves will be crushed.
In the Subspace Emissary
Outside of the above, Brawl's Subspace Emissary features several levels with crushes in them; owing to the mode's focus on platforming, the player is tasked with correctly timing their movements as to avoid these crushes. The following stages have crushes:
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