I thought this was really fun! As others have mentioned, the progression and exploration works really well, and there's a number of surprises to give some interesting encounters, like the random boss and kappas, very good stuff ^^
I went through all the exits I knew of but didn't find the dragon yet. I beat the reaper boss though, which was pretty tough? Pretty impressive how well this works, I'm sure the randomization was very difficult to implement :O
Monster goo is a good universal healing item name, everyone knows of healing goo XD