Falling spike

Falling Spikes are spiked obstacles that fall from ceilings, and appear only in Super Mario World but the Icicle from Mario Bros. can be considered a precursor. They are found only in Castles and Fortresses, and are typically grouped together amongst standard Spikes. They are slightly off-color compared to normal Spikes. Falling Spikes will remain on the ceiling until Mario or Luigi approach one, which will trigger it into falling, similar to a Thwomp. Once it falls, a Falling Spike will continue to fall through the floor until it disappears. They are darker in color than normal spikes.