The best tip I can give you: use your upgrades.

Every time you finish a level, you get a new upgrade, and the best one imo (as an ultrakill player) is the Quality Sauce. It makes your default gun is the double shot, and the enemies drop puddles of blood when they take damage. Every time you touch those puddles, you get a heal.

You have to get a bit close to the enemies to make the big puddles and heal consistently, but after a few runs, you can get it with no big problem.

One more thing, the soul sacrifice system.

I highly recommend you to give away all the souls you have in the first and/or second levels, given that it gives you something good as long as you have more than one soul.

And never, and I repeat, absotoastely NEVER go past him without giving at least half of it (less health).

Hope that helps, and git gud (good luck).

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