>>51392305I mean think about it this way, going in blind most players will probably enter against the Sudowoodo with a Fire, Flying or Bug type (or Ice if its early) if they're using set mode, the Sudowoodo's STAB Rock-Type attacks would pretty handily deal with those Pokemon, and in case the player either swaps out in anticipation or is using non-set mode and swapped to something like a Water or Ground Type then the Terastalize Sudowoodo would now resist them and have a super-effective move.
I dunno if that's how it'll work in practice but that seems like the intention, barring Poison-Type a Terastalized Sudowoodo can pretty handily deal with both its Rock-Type weaknesses and Grass-Type weaknesses.
