The Backrooms

Lvl 0

Wallpaper lvl 0 = smooth sandstone

Wallpaper with long stripe lvl 0 = birch planks

Wallpaper with short stripe lvl 0 = bricks

Carpet lvl 0 = Hay bael

Roof = Diorite

Lvl 0.1

Red = Roof lvl 0.1 = Smooth_granite

Red wallpaper with short stripe lvl 0.1 = Smooth_andesite

Red wallpaper = Sandstone

Red wallpaper with long stripe = Carved sandstone.

Hearts

Hardcore hearts

Icon in game

Buttons

Background

And more+
This Backrooms texture pack for minecraft v1.8.8, 1.8.9 and above contain