I had absolutely no ****ing clue what "Stalfos" or "Pols Voice" was, as this was my first Zelda game, so I remember getting so frustrated. Finally someone at school told me what it meant. I called those enemies the weird looking rabbits and the skeletons, why couldn't they have just done that? >.> Course now after playing almost every Zelda game in existence, I have the bestiary pretty well down.
I used to spend many hours trying to figure out what "stalfos" and "Pols voice" was and just hanging around that room with the bunny and skeleton. It took me 2-3 years until I first went to the Internet for a guide. I was like 10 years old.
I had problems knowing the beast terms as well, but it didn't take me forever to get the key in the room. I just killed everything in different orders until it showed up, but of course it took me till one of the last combinations.
I saw the answer before I even got a chance to play the game for the first time. Now I know it's just making a check for each enemy in the order that they are introduced in the room. That means the Pols Voice is the first entry, and the Stalfos is the last one. The Keese is second, but nobody cares about the freaking bats.
Actually now that I think of it, the first time I played the game, I thought it was referring to the boss and mini-boss. Pols Voice being the Cyclops thing, and whatever the boss was (eventually being the Genie), being Stalfos.