I absolutely hate tentacool. when I was going all over sinnoh to get misprit, I kept having to use surf, and EVERY TWO MOVES one would attack. even if I used repels. it took so much longer than I wanted.
other pokemon I hate: bidoof, wooper, wurmple, most bug pokemon, most ghost pokemon, MILOTIC(one pwnt me in ruby..three times in a row.), the entire pikachu evolution line, goldeen, tentacruel, gyrados, dialga, shroomish, breloom, spinda, cascoon, zubat, golbat, crobat, girafarig, and most of all, the entire marill evolution chain.