A burning companion that jumps to a new target on every kill. The Wisp starts on one enemy, burns it down, and then moves on rather than expiring. In a dense wave, a single cast can spread Burning through an entire group before you've fired a second shot.
Strategy
Cast it at the start of an encounter and let it work while you handle other threats. It pairs naturally with Surcharge: the Wisp spreads Burning to multiple enemies, then one Surcharge detonates all of them at once. Its long cooldown means you want to deploy it early in a fight rather than save it.
Strengths
Single cast can spread Burning across many targets via kill jumps
Requires no aiming after initial placement
Exceptional setup for Surcharge detonations
Weaknesses
Long cooldown for an autonomous unit
Stops spreading if it can't find a valid target to jump to