I don't think gamepasses are allowed, so this won't have any gamepasses or event items involved in this.
The easiest way to practice is the skip loading trick. It does not remove the loading screen, BUT you can move while it's still loading. Just memorize each path that you have to go down with the skip to get further ahead!
The second way is to try and memorize each level and path. This is heavily required with this run, as things get randomized. I suggest studying a map from the wiki to help!
The third way is to practice doing each boss as fast as possible! There is a trick to this, pull out the sword and spam click while moving your camera slightly. This will do some extra damage to the boss.
Good luck!
With the edition of Retro Resort Cluster II It has now been added to the Retro Resort Category. I may add 1-20 in the future but similarly with the main categories it main result in a situation where the end goal keeps getting shifted and the leader board would get continually wiped every year. Alon