Key:

https://opengameart.org/content/blast-off-space-shooter-sprites

Ammo Clip:

https://opengameart.org/content/cc0-flat-ammunition

Ammo Pack:

https://opengameart.org/content/ammo-pack

Health Pack:

https://opengameart.org/content/healthpack-0

Treasure:

https://opengameart.org/content/gold-treasure-icons-16x16

Food:

https://opengameart.org/content/some-fast-food

Dog:

https://opengameart.org/content/wolf-pack-32x32-walking-wolf-animation

Guard:

https://opengameart.org/content/psycho-man

SS:

https://opengameart.org/content/mark-2d-adventure-game-sprite

Officer:

https://opengameart.org/content/8-directional-sprite-sets

Mutant:

https://opengameart.org/content/husk-mutant

Ghost:

https://opengameart.org/content/evil-ghost

Bosses:

https://opengameart.org/content/cartoon-male-turn-around-and-walk-cycle-...

Square Table:

https://opengameart.org/content/table-to-do-the-only-thing-worth-it-in-life

Circular Table:

https://opengameart.org/content/pixel-art-circular-table

Potted Plant:

https://opengameart.org/content/low-spec-fan-palm-potted

Cage:

https://opengameart.org/content/misc-dark-fantasy-scenery-sprites

Barrel:

https://opengameart.org/content/pixel-barrel

Well:

https://opengameart.org/content/well-3

Spears:

https://opengameart.org/content/spears

Lamp:

https://opengameart.org/content/lamp-post

Bed:

https://opengameart.org/content/random-assets-0

Vines:

https://opengameart.org/content/vines

Bucket:

https://opengameart.org/content/quick-32px-sprites-bucket-nest-wood-seed...

Vase:

https://opengameart.org/content/various-containers

Kitchenware:

https://opengameart.org/content/lowpoly-kitchenware

Blood Puddle:

https://opengameart.org/content/simple-blood-splatter

Prisoners:

https://opengameart.org/content/people-being-tortured-0

https://opengameart.org/content/unfinished-gun-sprites-in-gif-format

It doesn't do anything, that's the beauty of it.

https://www.youtube.com/watch?v=XgJhm5zFDzQ