Resident Evil 0

First of all, this can be done on easy (As well as 'Save your prayers)'. Easy makes the game an absolute joke compared to even normal. Zombies die in roughly 3 handgun shots, ammo is EVERYWHERE (As well as health items, but if you are going for this achievement, you will sadly have to pass up on them). For the most part, if you have played through before and you know where tough encounters and bosses are, you shouldn't have too much trouble with this achievement.

Pro tips:

1). Play as Billy when fighting. Even after taking multiple hits throughout the game, Billy was still fine by the end (Rebecca in yellow caution with less hits taken).

2). Be VERY careful around the spiders as they can poison you. If you aren't going for the Save Your Prayers achievement, I'd recommend saving before you go behind the painting due to the fact that if you get poisoned, it is game over. Thankfully the spiders only appear in the tunnel behind the painting and the tunnel outside the battle arena. Kill them on site. It should take 1 shotgun blast on easy difficulty.

3). Kill hunters with a powerful weapon. As you probably know, they are fast and can do a lot of damage very quickly and are even capable of stun locking you. Luckily, a blast from one of the big guns knocks them back, allowing you to blast them back down once they get up from the first shot.

4). If you are planning on saving, do so before the giant bat. It isn't the boss that is hard, it is those stupid smaller bats, damaging you and messing up your aim so the big bat can come in and attack. I recommend saving before incase you feel you took too much damage, you can try again.

5). At the end of the game, a little before the first Marcus boss battle you will cross a bridge over water. A lurker (giant frog) will jump onto the bridge. KILL THIS IMMEDIATELY. If it grabs you with its tongue, it will pull you in and kill you instantly. Do not fight it alone, that way even if you do get grabbed, your AI team mate may be able to save you.

Everything else is just a matter of learning the game and playing it safe. I recommend either playing the game on easy, or if on normal, completing S rank first so you have the infinite rocket launcher. You can stack this with Save Your Prayers if you feel daring, but you can do each achievement on a separate run to make each one less stressful.

This can become an easy achievement with my strategy. In Leech Hunter collect 100 leeches to get the top prize. You can choose to play it safe by doing this on easy difficulty. Now very important do not use the green chemical as a health item.

You have to use it to create important stuff. Other than that it won't count your process. You also can pick up health items, I personally avoided doing that the entire run. If you don't have the rocket launcher unlocked.

You still can get very far with magnum revolver, another prize from Leech Hunter. Just like the other magnum found later on, it will one shot most enemies. Depending on difficulty, it shouldn't take much more shots on some of the bosses.

Billy is notably tougher than Rebecca overall. I would make sure for most of your run give her the stronger weapons. It is possible to prevent getting hit by both forms of Queen Leech. You can get her stuck in an area by firing with stuff like magnums, grenade launcher & rocket launcher.

I also highly recommend doing a couple of runs to memorize the game to the best of your ability. Thankfully you can prevent taking damage with most of my strategy.

Here is a link to a full walkthrough of RE0 on Hard difficulty that achieves an S ranking. It features no healing and full commentary allowing players of any skill level to emulate the strategies and get this tricky achievement.

https://www.youtube.com/playlist?list=PLTaOHX8kEkD5K78KlKZOM...

Hope this helps.

I got this Achievement Playing Wesker Mode. Also had infinite Ammo Unlocked as well. Pretty Simple Achievement for anyone to get. Just don't Heal Yourself!! lol. U can use Wesker's Death Star to make it more easier. I also used the Magnum Revolver as well that u find on the Train. Once u beat the Game. The Achievement Will Unlock. Perfect Runs for Not Saving, or Using Frist Aid Spray. Here is a Full Walkthrough Video of me Unlocking it in Wesker Mode :)