I think it might be a memory leak, or just excessive memory usage.
LoneBone
Recent community posts
* Each time you die, look at the board, see if you spot a hint or pattern. There are plenty.
* You can count the time until you need a heart scroll by comparing xp row to heart row.
* Save the scrolls as long as possible. A late game scroll is worth a lot more than an early game scroll.
* Bashing walls is an absolute last resort
* Look at squares, do simple math, check the book to see what monsters are still around.
I know the "cost goes up exponentially for no reason other than because cookie clicker did it" is the default in the genre. But in a science fiction setting, centered on a real scientific concept, it felt jarringly incongruent. The concept of the probe is - go to a place, look around, make some copies and send them to more places. Spread like bacteria. The "cost" of each new probe is the same as the first one, or lower if there is any kind of learning or feedback in the loop. It can be taken in many directions, but exponentially growing marginal cost isn't really one of them.
Cute game. Enjoyable. Balancing the difficulty scaling in the current design might be hard though. As it is, you will lose early if you make a mistake or have bad luck, but once the horde hits critical mass, it's a curb stomp. The entire scaling mechanic needs to be different if you want to avoid that.