Sisyphus Prime (Second Boss) Guide
Think of him like a souped up Ferryman. A very large, very teleport-spammy, relentless Ferryman maybe, but the same tenets apply; let him come to you until you’re extremely comfortable with the rules and timing for his predictive attacks or else he’ll fly all over the place.
There are two major things to keep in mind: one, even though a variety of his attacks come from random directions in front of you and push you to the ground or away if they land, he will only vanish if he’s about to slam. Two, he’s less consistent in phase 2 because he can cancel his attacks into each other more frequently and more quickly, like “You can’t escape” leading into the teleport stomp being a prominent thing to watch for.
With this information, you shouldn’t stand still unless you’re ready to dash on reaction, should otherwise be moving quickly away in gentle curves, and remember that if he straight up VANISHES then that’s your cue (or lack thereof) that he’s going to stomp where you were headed. If you’re not holding down slides and wasting dashes, there’s just barely enough time to recharge stamina in the event he does a mean combination of moves. Also remember that you get a speed boost for converting a slam into a slide right after you land, so when “You can’t escape” randomly chains into the teleport stomp, take advantage of this to quickly change direction.
In less words, spam slide in a curve away from him to outspeed him, dash on reaction for the moves that will slap you for doing so, and if you’re forced in the air, get back on the ground as soon as possible since the ground means sliding and being able to juke him without burning resources.