KDL2:7-6

Captain Stitch

This is one of the most notoriously difficult & RNG heavy fights in the game. Captain Stitch has a lot of invincibility frames (58 frames of invincibility after getting hit) and they can only be damaged once they either throw their spike or charge into a wall. Their charge attack is the easier one to deal with overall but will still take practice to get down. When they throw their spike, you have just enough time to damage them twice and drop your ability to combine it with the spike for a double star, which will kill them with the next attack they do if you were successful with getting the 2 cutter hits in.
Stitch can also fly around a ton before throwing his spike, however this can potentially be avoided. If you position Coo around 4 tiles away from Stitch while on the ground, if they decide to do their spike attack, Stitch will throw the spike instantly making it more consistent. Using this with great reactions and timing, you can optimize the Captain Stitch fight to be a lot more consistent.
Optimized 7-6 Captain Stitch fight: