I'm surprised no one has brought this up over the years very much (let alone, fixed), but... there's a few more bugs in this game. Some good, but a lot of bad.
The upgrades are really needed in this game as enemies get stronger as the game progresses. You have a limited amount that can be thrown as a bar depletes with each throw. Money can be a bit tricky in this game as well as the prices for these upgrades increase as well for each floor, but luckily, the bar is completely refilled after each floor as long as you still possess that upgrade.
That bug was really helpful and I didn't even bother with the money anymore, but around floor twelve, I was met with a dilemma as I ran out, so I began to gather money once more. I was around 41 at the time, but the upgrades went up to as much as 114. This was not much of a problem as I was quickly gathering money over the floor, when suddenly, my money was reset. I didn't lose all of it as it went back to somewhere around 17, but I was nowhere near the store. In fact, I was locked in a room with a monster.
Irritating bug that one was, but that fails to even compare itself to the greatest bug this game suffers with. When one enters a room, they're pushed into it before spikes lock you inside. However, on three separate occasions when I entered a room, I was pushed out and locked out, making it impossible to enter the room (four if you want to include that a monster was pushed out of the room and locked it outside, but me inside). This issue is the worst as I find myself in a spot where I can't continue the game, because between me and the ladder to the next floor, there is a locked room that I can't enter until I kill the monsters inside that room. This issue made me restart when I was on floor eight, got lucky on fourteen as the ladder was in another direction, and made me end the game on seventeen.
For what it's worth, the game is alright at setting a tone, but there are some bugs that cuts this game short.