Lava Steam

Steam jets are obstacles that appear in Super Mario Galaxy, making their first appearance on the Yoshi planet in the Space Junk Galaxy. They are small mounds with holes in them on the ground or on walls that periodically release hot steam. They are safe to touch in their dormant state, but if Mario or Luigi touches them in their active state (which they switch to after a second of warning in the form of weaker steam that is safe to the touch), he will catch fire and run around uncontrollably while losing a wedge of health, in a similar fashion to touching lava (or any other fire-based danger). They are most common throughout the Melty Molten Galaxy, but they can also be found less frequently in other galaxies such as the Freezeflame Galaxy and on the Lava Planet in Bowser's Galaxy Reactor.