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Since Mankey is on here at all, it really should be added to the 25 Speed tier, since Scarf is its most common set. Also, Jolly Tirtouga should probably be added to the 12 and 24 Speed tiers.
OP, you took my thing! Come on, son. Speed tiers are obviously my thing. Just because I haven't been on much in the last year doesn't mean you can take my thing. Squirtle is cute though... You did a good job too. So I guess it's okay. I give my stamp of approval. (QC 1/3)
Scarf Vullaby should've been added by now, as such as this set is listed on his strategic page and also many people are considering to suspect it, that's why i think it should be added to either the 22 speed tier (adamant nature) or the 24 speed tier (jolly nature).