I think you are mistaken,
Antonykun
, the monkeys aren't the Gen 5 starters. They're just glitches in the system and will probably be taken out in Gen 7
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Also Grotle is the second stage, Turtwig is the first.
Lavani
just played quite a few games against a fairly skilled Rosalina on FG (IMO, I don't have a lot of experience to compare against; he used a lot of grabs but not a lot of jab, but was proficient at what he did). I lost most of the games (I only won two or three, one of which was this rather fraudulent game where all three deaths were stage spikes lol). Went Game & Watch for all of them and learned a lot. I'm happy he stuck around for as long as he did, especially after the disastrous first few matches. A lot of times good players will leave after they beat you a few times which makes getting practice hard, but he didn't which gave me time to adapt and learn. He was actually the one who left after I won a match; I was willing to do at least one more because I get mad at players who beat you once after losing a lot and then leave
I've stated that I feel like the MU would be even without Luma before, but now I don't think that's the case. Rosalina's moves and attributes are pretty well set to handle Game & Watch. Luma adds three main things to Rosalina against G&W: added hitboxes, more power (a biggie), and resistance to throw combos (which is frustrating since Rosa would be complete combo food from it without Luma). But Rosalina walls G&W out pretty well by herself.
DAir makes challenging his recovery pretty free so he's got to get to the ledge as soon as possible. UAir practically always beats his DAir (not that you should land with his DAir frequently but eh). Full hop aerials can rather easily be caught with dash attack or USmash. Basically her hitboxes tend to be positioned just in the right place to counter his attempts at approaching, baiting, or counterattacking. Additionally, his usually fantastic USmash becomes a LOT less fantastic in the matchup because many of her attacks hit low enough to hit his body (dash attack, DAir, and I think USmash are the most notable).
Basically she's one of the few characters that can consistently outbutton Game & Watch, the one thing he's typically great at. A lot of his usually staple moves become less useful in the matchup, too, although dash attack and BAir are still handy.
I really think if I could learn the character she'd be the one who best fits what I like and what I do of the top tiers, with the disjoints, long recovery, flexible air movement, and traps. But I know she's not easy to pick up and even though I'm starting to feel more comfortable with her she's not a character I feel natural using. So I'm going to stick with my current choices and see what I can do with them.
Also, necessary riffing on her design. One, she has duck lips. Two, her star KO scream sounds hilariously fake "ahhhhhhhhh." No emotion in it). Three, I really want to see her hitbubbles once we get a viewer, dash attack and USmash seem to have these airbender disjoints that overly protect her during them.