Little Bones

From itch.io:

Basically Maze Rats with a dusting of Tunnel Goons and a large spoonful of Basic Dungeons, but stripped back to fit on a double-sided A5 page, and sped up for one-shots, picnics, and parties. These rules work great with both kids and adults.

Little Bones is played with 2d6. If you would like to play this game with, say, a single giant foam d12 instead then try Big Bone.

Includes pre-rolled characters, a spell generator, stat suggestions for creatures and NPCs, and an adventure builder.