I know a while ago I wrote my top 20 somewhere, but I'll try to do it off the top of my head.
1) Tyranitar
2) Bidoof
3) Swellow
4) Scolipede
5) Gallade
6) Typhlosion
7) Xatu
8) Tropius
And this is where it gets fuzzy, so I'll just list 12 more I really like.
Alakazam
Bulbasaur
Haxorus
Vileplume
Poliwrath
Gigalith
Kyogre
Swampert
Mienshao
Spheal
Teddiursa.
Slowbro
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