this is a Addon from Minecraft 2009 of 2010
example mobs, items and blocks, this one is a Nostalgic called Nostalgic Craft.
Spider - from Survival Test 2010
Zombie Pigman - Pre-1.16
Human - 2009 Classic
Pigman - Indev or other game from 2009
Slime - 2010 has been added the old texture
Pig - example from 2009 old texture
Cow - 2009 but has no horns
Blocks - Old famous Textures
Gravel - changed texture into 2009 game
Cobblestone - changed texture into 2009 game
Added Ruby into the game
Added Raw Beef and Raw Porkchop
Added Cooked Beef and Cooked Porkchop.
Added Block of Ruby and Ruby Ore