Plague Cauldrons are a platforming challenge in Shovel Knight found primarily in the Explodatorium. They are dark vats of purple liquid covered with a lid that acts as a platform. At regular intervals, the cauldrons will boil over and propel their lids into the air. Some cauldrons have spikes on their lids that will damage (but not instantly kill) the protagonist. Getting in between the cauldron and its falling lid will also damage Shovel Knight.