The thing about this thread is that anybody who wants can just grab the answer in Hackster.
(And about the "rarest enemy" thing, I have read that, technically, it is TRex; due to a CPU bug in the NES, you have to get step-count of 255 in order to run into one. It's certainly possible, as the 6502/2A03 is full of quirks, like the fact that unimplemented opcodes actually do things.)