Spasmodic is a fun geyser. It erupts from at least 20 vents. During the eruption, the activity overall is nearly constant but the activity cycles through the various vents every few minutes. Some vents only erupt a few inches while the tallest can reach ten feet. Intervals are about 1 to 3 hours. Durations range from minutes to hours. Spasmodic is in eruption about one third of the time.
Spasmodic is active during both the Sawmill Mode and the Penta-Churn Mode. In either case, Spasmodic usually precedes these other geysers.