leaving this for future reference.
i was ready to give this a score of 0, until i went and got all the medals; the difference between having an absolutely dreadful experience and a somewhat bearable one is knowledge on how the game works, so i'm going to share everything i got:
things to note:
- there is no invincibility after getting hit, so running through obstacles after getting hit once is a bad idea. standing into an active hitbox will continuously deal damage, so the best way to survive is to run through obstacles while trying to stay as little time as possible into their active hitboxes.
some of them are simply unavoidable, so instead of timing them, sometimes it's just better to take into account how much health you have and tank through them, trying to stay into them as little as possible.
- you naturally recover health (VERY SLOWLY) but sometimes it's necessary to just stay put in a safe spot and heal before tackling a series of obstacles, otherwise you'll just be forced to go back to a previous checkpoint and go through them all over again.
schythe monsters deal 50 damage, rockets deal 20 damage. these are notable because a few of them are unavoidable (brick wall section) so you should be mindful of having at least enough health plus 1 before running through them. you may need to straight up stay in a safe spot for a solid few minutes just so you don't have to restart all over from a checkpoint.
- ceiling traps are tricky: when you walk under them they activate and make purple spheres fall to the ground; the individual spheres are what deal damage, and they fall at random.
after some time the traps will close and be ready to activate again.
running through while activating ceiling traps will force you to take the brunt of the damage, as you'll run into all the purple spheres that fell.
the best way to avoid damage from these is to activate them by barely walking into their range, get hit only by the spheres that fall on the side, then walk past after all the others have disappeared and before the trap closes again.
this is especially important when you'll find multiple ceiling traps in a row, and you'll need to walk past them all at once.
1. the first run should be an all-coin run. you're gonna need to explore the entire map to learn the layout, what's the most efficient way to gather all the items to progress and which roads can be completely skipped over. it's gonna be tedious and take A LOT of deaths, as some coins can only be accessed once, so if you miss the jumps you may want to die to restart from a previous checkpoint.
some parts of the game also lock you out from previous parts of the map after reaching certain checkpoints, so you may find yourself forced to restart the whole thing if you miss some coins along the way.
this took me two tries due to missing some coins and getting locked out by a checkpoint, and about 90 in-game time minutes on my second run. you're also going to need patience (and i mean A LOT), as the majority of traps are straight up BS the first few times you go through them.
2. second run should be finishing the game in under 50 minutes. after knowing the layout, and knowing that you're free to die to use checkpoints to get around the map faster, it took me about 30 minutes of in-game time, so it's fairly feasible.
it's to note that by abusing checkpoints, i also managed to clear the game "without dying" in under 50 minutes, so it really shouldn't be that difficult to get.
- the "immortal" achievement is obtained by clearing the game in a single sitting, REGARDLESS of how many times you die.
this means that as long as you don't exit out of the game and don't go back to the menu, this is the best time to get it. you're allowed to die as many times as you need, as long as you finish the game in one sitting (you can still pause the game/tab out of it, as long as it stays open)
3. last run should be to get the "no knives, no guns, no saws" medals. i'm not actually sure what's the exact requirements for these, as i did die once on the last section from bullets and i still got all three.
you should still try to avoid dying at all, as it's possible to clear the game without dying by abusing checkpoints.
- some checkpoints don't actually save your progress. when touching a red totem you should pay attention to whether the game says "game saved" or not.
after you've saved at a checkpoint, if you happen to die you can close the game, re-open it and continue from the last checkpoint that actually saved your game; you can abuse this to get at the very least up to the last section with 4 switches before the final door without dying.
since you have no time constraints, and no need to collect coins, remember to make use of the EXTREMELY SLOW regenerating to make sure you're healthy enough before tackling difficult obstacles sections.
sections that are especially difficult to get through are the brick wall one (as you'll need to go back and forth multiple times to make the bomb, without being able to teleport to a checkpoint by dying) and the section where you collect the magnet item, where you'll need to do a lot of waiting and regen to stay alive.
- as long as you manage to get to the last checkpoint with no deaths, it's probably possible to get all three medals even if you die a few times while trying to hit the switches on the last section.
you should be able to unlock them one at a time by making sure you are clearing the game while not dying from one of the three requirements, then continuing from the last checkpoint.
that's about it; good luck to any brave soul attempting these.
Yemita 
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