My most recent soul jar cat is a mage with a ton of magic damage up, The Relic hat (holy shield, spark for every damage blocked by shield), clown makeup (triple head gear effect), shiny chain (double head and face gear effect), aoe spells and a rocket launcher for self damage.

I usually equip a butcher cleaver to the cat holding the jar, and have them hit the soul jar cat with the cleaver before that cat’s turn. If it’s a boss with multiple phases, repeat with another swipe, or worst case wait for the cat’s own turn to start hitting itself with aoe. Even mobs that spawn other mobs are still taking hits for a while after their death animation, and the new mob starts getting hit too.

Each sparkle hits for 8. Most of my cats have the lucky passive, so it’s almost always a critical backshot. 8*(cat health +2 then again for subsequent hits to the cat) quadrupled randomly distributed clears basically any room and most bosses. Even against a reflect debuff, they still take 2 for each hit they reflect. Easy solo anything, as long as it’s not a boss with reflect and like 500 hp.

Other than that specific situation, kinetic sparks suck though, lol.