Sudowoodo in depth
The liar and the tree
ウソッキー is read as “Usokkie” and combines 嘘つき (usotsuki, liar) with 木 (ki, tree). English reaches the same place by a different route: pseudo plus wood, fake plus timber. Both languages say exactly the same thing, and neither bothers to hide it. This is a Pokémon whose full name is an accusation that it is lying.
The official category, Imitation Pokémon, rounds out the idea, and the rest of the design draws on bonsai: a small tree, pruned and cultivated for display. That reading is much clearer in the baby, which is literally a little tree in a pot with tears, than in the adult.
The tree that would not let you through
In Gold and Silver there was an obstacle on Route 36 that looked like scenery. If you examined it, it shook. Cut did not move it, Strength did not move it and there was no way around it, because it was not a tree: it was this Pokémon planted in the middle of the path, doing its routine. The solution was to wet it — a florist's SquirtBottle, or the Wailmer Pail depending on the version — and then the battle would start.
It is a one-off specimen per save file, with no second chance if you knocked it out. That detail turned a comedy scene into one of the moments in Johto where the most people carefully spent their Poké Balls.
The baby that arrived two generations late
Bonsly did not exist in Gold and Silver. It appeared in Generation IV, as part of the wave of baby pre-evolutions, and brought with it an evolution condition that suits the character: levelling up while knowing Mimic. Imitating in order to stop imitating. It is the same recipe that turns Mime Jr. into Mr. Mime, and in both cases the move has to be in one of the four move slots at the exact moment the level-up happens.
The type, on the other hand, has never changed. Pure Rock since 1999, with no secondary type, regional form or variant of any kind — it only has one recorded form. Very few Generation II species can say the same.
What to do with 30 Speed
Almost all of its useful movepool assumes it will move last, and there is a way to play around that. Counter, at level 40, sends physical damage received back at the attacker and works better the later it is used. Block, at 12, prevents switching and is useful for trapping an opponent that cannot do anything to it. Sucker Punch, at 28, is the opposite: priority for finishing off anything that is fast.
Compared with Golem, the other slow, hard-headed rock, it loses out where it matters. Golem has Ground as a secondary type, which gives it a STAB Earthquake and offensive coverage that has to be sought out through TMs here. In return, Sudowoodo does not carry a quadruple weakness to Water or Grass, although with two double weaknesses to those same types, that consolation does not go very far.
The other piece worth mentioning is Stealth Rock via TM. A physical wall with 115 Defense that survives a turn to set the rocks is a perfectly reasonable use in a normal playthrough, and the three elemental punches — Fire, Ice and Thunder, all via TM — cover a good part of what gives the Rock type trouble. They do not turn it into something else, but they give it answers where before there was only 30 Special Attack.