Yeah, I think really the easiest way to do that kind of thing is to either pull the Color Splash thing where he just kept summoning minions while doing mostly nothing on the smokestack, or to pull what mainline games often do and... make him easier than the rest, which I imagine is done to show that he's not really in on it, so it's difficult for him to focus on it (but of course, does a poor job at conveying that because they don't really put dialogue or anything like that).
The best that mainline has conveyed this bit of Larry's character was in the Super Mario Bros 3 Japanese instruction booklet, with him saying that he's doing what Bowser says because he doesn't wanna be yelled at, but Color Splash's dialogue (in Japanese) does a better job of conveying this, having him outright admit he wanted to rest instead of fight but feels like there isn't any helping it because of the fact Mario showed up, so he thinks he has no choice (and ultimately I think that suggests the choice is on Mario, but Mario misunderstands him as being dishonest ALA Hooktail in The Thousand Year Door or the crumpled Paper Goomba in Paper Jam so Mario fights anyway, of course, as Mario wouldn't see all the consistent ties with his behavior since he doesn't know him well), then go on to say "If I don't defeat you before the train reaches starlight cape and bring back the big paint star, scary Lord Bowser is going to scold me!".

















and the flagpole height



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