item drops from enemies & the item room are totally random, but some items are rarer than others (like the +1 max HP). You totally can get as much HP as you wanted if you play for long enough. Though, im not quite sure what would happen if you got to the 32k integer limit in PICO8...
We had lots of fun using PICO8 for this game, but I am so ready to not use it for my next project lol. We were basically always right at the 8k token limit right up to the end, had to make a lot of silly optimizations and sacrifices to get it to fit
Thanks for playing!