I've tried reinstalling the game twice, rebooting my computer, and nothing. Steam says "Preparing to open toribash", and when this message goes down, nothing happens, not even a Toribash process.

1. Close steam and overally make sure that it's off
2. Go to steam folder
3. Delete ClientRegistry.blob file
4. Launch steam

It should work

Go to your toribash folder on steam and try to open toribash.exe, It'll probably show an error, screenshot that and post here

I had this issue a couple months ago. What I did, was reinstall a different game besides toribash on steam, and it canceled Toribash and rebooted it.