Different from slow rising grey color campfire smoke, potent sulfur's white sulfur dioxide smoke is fast, thick, strong and toxic, it will cause poisoned or suffocation affect on creatures stands on top of it, It can be used as a scene prop for volcanoes, fire areas and industrial chimneys.
So player can place a water with bucket underneath to trigger a geyser erupt boosting player jump forward while running or step on a pessureplate that power a piston to push potent sulfur/magma block to form a geyser to erupt as soon as player jump on top of a geyser
Different from water geyser, lava geyser is extreme dangerous, the potent sulfurs and magma blocks combo will generate in nether's lava area in small amount