so if Lip is playable she should be grown up.
I'd like that as well, but it also has quite a few extra roadblocks.
1) Main look. It's really hard for even me to imagine how Lip would look grown up. All we have to go off of is her look, her mother (Corderia)'s look, and the fact that she (Lip) would be Queen of Popples if shown fully grown.
2) Avoiding cloniness. A Stick-based moveset works best here, but that's probably going to belong to Krystal. So, keeping her from looking too much like a Zelda/Mewtwo clone in her A moves is essential (the B moves would be pretty easy).
3) Stat Balance. This is much more difficult for Lip grown up than Lip as a child. Seeing that she'd probably be a really tall character (if Corderia is anything to go by) and rather lightweight (probably about as heavy as Peach or Zelda) it'll be pretty tough to offset these 2 drawbacks. While "Large Target" and "Lightweight" aren't much alone, they are devastating together.
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Speaking of hugeness, after managing to watch
this from start to finish I'm starting to think that if Corderia showed up as a boss in the Subspace Emissary, I think I'd **** my pants... Especially if I can't use Lip, Yoshi, or Falcon (the latter 2 are my mains) in the battle.