[Resident Evil Zero HD Remaster] Leech Hunter, Hard, All Enemies/Leeches Trophies, No Damage, A Rank

Resident Evil Zero HD Remaster - Leech Hunter

Hard: highest difficulty
100% / A Rank: 100 leeches collected
Kill All Enemies: kill all enemies (with respawns* - more info on locations below) to get "Distracted from the Hunt" trophy
No Damage (for both characters)

The run follows this script:

Kill all enemies (first pass) (0:00:00)
Collect 50 leeches for Rebecca and 40 leeches for Billy to trigger respawns (0:48:57)
Kill all respawned enemies* (01:05:25)
Collect the last 10 leeches for Billy (01:16:52)

Respawn enemies locations: 01:05:41 , 01:07:47 , 01:10:12 , 01:12:05 , 01:14:18 , 01:15:18 , 01:16:17

Several tips for no damage runs in this mode:

There are different RNGs for the items in this mode. For a no damage run, you want the ones you obtain the machine gun. Basically at the beginning, you need to see two green herbs at the main hall, which is an indicator of machine gun/acid rounds RNG.
Billy AI is a lot more aggressive than Rebecca AI. In the rooms you need to be aggressive to avoid getting hit, you want to control Rebecca and have Billy AI helping you. In situations you want to conserve ammunition, you may prefer a more passive AI casually assisting you.
Billy is more efficient shooting with faster recoil animations.
Use the knife on most zombies playing dead to save ammunition.
You deal more damage by shooting enemies close range even with the pistol.
There are several handguns in the run. I recommend discarding the weaker handguns as early as possible to conserve ammunition. Before discarding them, try to waste almost the entire clip. Pick up the stronger (and faster) pistol - Custom Handgun - as early as possible to make each handgun bullet count.
The AI is very good at detecting when enemies are dead when using the machine gun even in camera angles you can't see the enemy, so in several rooms, I'd advise having Billy AI using the machine gun to save ammunition.
The acid rounds are very effective in key situations since it can guarantee stuns on hunters. You want to use it wisely saving ammo for situations you need to control. Having Rebecca with acid rounds and Billy AI with machine gun is a great combination against hunters waves because you control exactly your acid rounds to effectively stop them from hitting you while Billy uses machine gun ammo precisely detecting when they're dead to save ammunition. Examples - 0:15:26 , 0:28:00
The positions of both characters in the room depend on what character opens the door. In some specific strategies in this run, you will see me entering a room with Billy, switching to Rebecca, and use his AI in a more favorable position (example - 0:16:43). This is mostly because the AI gets more aggressive when enemies are close and will start shooting early.
Don't enter this room (0:12:51) with both characters or you'll get grabbed instantly by a zombie on the ground.
In this mode, enemies don't reset their HP value if you get out of the room and return. So if you're overwhelmed, don't hesitate to reset the room. They also reset their positions, unlike the main game - in most cases. Example - 0:14:14