Effect
Summon a companion to fight with you Gain Storm Cloud with a +20/34/48/61/75% chance when a lightning arrow hits an enemy.
What Mini Ballista does
Mini Ballista is a advanced-rarity artifact in Sephiria. In the inventory grid it occupies its own space, and any tablets you place beside it multiply the effect shown above.
It counts toward the Companion combo — pair it with other artifacts tagged Companion to trigger that combo's set bonus during a run.
Data source
Effect text and rarity are taken verbatim from TEAM HORAY's Fan Kit catalog (game build 1.0.25, indexed 2026-08-11), reproduced for reference. We do not add inferred numbers or unlock conditions that the Fan Kit does not supply.