An interesting little, I assumed high score game. But I guess just survival game where the goal is to get out with the coins you need to pay the portal. I was more expecting it into be a matter of aiming to get the most coins within the time limit and escape through the portal. That way it's a risk vs reward setup where you want to get as MANY coins as possible, without losing every single to the time limit.
Onbe other thing I would say is that the chests being randomized in their loot, is a little weird. It feels like a little bit too much randomization combining with the spawning of the coins and such, as well as the time limit on top of the cost to leave. I feel like it would be a little nicer if it was more just "find the loot, it gives _" so that it's more consistent in what you're dealing with.
Cause at the moment it's possible to have to pay 15 to escape and then get multiple chests of 2-3 for example. Or whatever the minimum number actually is. Which means there's the possibility of a situation that definitely feels like there should be enough not having enough. Which is never quite fun as a player.
Otherwise though I would say a bit of map polish would be interesting, maybe more to interact with environment wise, some trees etc. Though obviously this is a jam, it's got a time limit so this is more stretch stuff that would've been interesting and added a bit more variety.
Overall though a pretty good jam all things considered and I'd be interested to see what else is managed.