Meltopia

 The world has frozen, and you've got a flamethrower.

That's effectively it in a single line.  Things you uncover in the snow might be upgrades or artifacts or reasons to dig further.   There is a "coldness" you have to contend with that adds a bit of a timer to your missions and the mazes are a bit chaotic to figure out because you traverse them a few times as they transform before you've melted all of the snow.

I found myself getting lost - it was fun but the last few artifacts I needed I didn't care to hunt through areas I had already scoured.