The Medusa Heads have definitely been extremely annoying since the very first game.
Fleamen, Crows and Imps come in 2nd, 3rd & 4th respectively.
BTW. I would like to extend a sincere and heart-felt 'fuck you' to IGA and Konami for that one room in the DoS Clock Tower that has both kinds of medusas, imps and a couple of fleamen. Go eat the rotten asshole of a road-killed skunk you douche nozzles. ^_^