"Any Number"
From Archon Arcana - The KeyForge Wiki
When a game rule or card ability states that a certain action involves “any number,” that number includes zero.
Likewise, if a card ability states a certain action involves doing something “up to” a specified number of times, the active player may resolve the ability using any number in the specified range, including zero.
—KeyForge Master Rulebook v17.4 September 2024