Meant to be part of #42864 , but got a little big so I'll add it to wichever gets merged last.
[Snailcrawl demonstration](https://youtu.be/IL7WFpfRo4c)
PROS
- Gets snailcrawl, wich makes them greatly faster and gives them a lube trail
- Their blood is spacelube
- They get a cool armored nodrop snail shell
- They don't slip
CONS
- Very slow
- Punch is pathetic
- Tttaaalllkkk llliiikkkeee ttthhhiiisss
- Extremely vulnerable to salt
- Can't wear glasses
Adds gastrolisis, wich is pretty much [this](https://www.youtube.com/watch?v=lFbPi8o0OEU) spongebob episode where they slowly turn into snails
You can also get gastrolisis by random_reagent_id, so maintpills and botany
🆑
add: Adds snailpeople as a rare genetics accident.
sprite: Snailshell sprites by nickvr628
/🆑
Snailshell sprites by @nickvr628
Why: It's a silly gimmicky race and it's a rare occurence. Also extremely highly requested for some reason
