A rocky vent builds pressure and periodically erupts a tall column of water and steam, misting the pool below. The eruption cycle runs through buildup, eruption and cooldown phases whose timing is expressed as fractions of a total cycle duration, driving vent rumble, glow color and light intensity. During eruption, thousands of particles are spawned from a ring-buffer pool with randomized upward velocity and gravity, bouncing gently when they hit the pool surface, while a separate low-density mist cloud drifts continuously and intensifies right after each blast.