This is a simple challenge where you have to run fast to get to the other side, useful corridor as part of a challenges area.
Stepping on the pressure plates at the start set off two mine-carts which set off pistons, which in turn make the floor for you to run across.
Crimson.nn.pe:25583
CrimsonDawnMC.enjin.com
CREATIONS
MINECRAFT-SCHEMATICS.COM