Unlike some (probably most) people here, I don't hate the Legends Of Bikini Bottom episodes. I just find them not funny and kinda dull. They are very unmemorable and that's my main flaw with them. But...I probably should have said I don't hate almost every Legends Of Bikini Bottom episode because one of them and it's easily the worst episode of the mini-series.
It's of course; Trenchbillies. This is a terrible, terrible episode. I'm not gonna go into detail on it since the main plot's so weak and forgettable, I don't remember anything about it except...of course, that it's bad.
It's not the worst episode of the season but it's up there. I find it worse than A Pal For Gary and I almost find it as bad as Yours, Mine And Mine. It's that bad.
The rest of the Legends Of Bikini Bottom episodes are just really dull and they have absolutely no humor. The Monster Who Came To Bikini Bottom is a nice friendship tale and it's actually somewhat heartwarming. Welcome To The Bikini Bottom Triangle is the best of the bunch. It's really interesting and there's a nice callback (or should I say, foreshadowing) to the first movie in which Patrick is attracted to mermaids. It's a nice little touch.
The Curse Of The Hex has a stupid ending which is the only thing that stands out from it because it's the most forgettable of them all.
The Main Drain is probably the most boring out of the Legends Of Bikini Bottom episodes but it's not the worst.
No, the second worst episode of this mini-series is Sponge-cano. Now, I really like Spongebob in this episode. He gives us a fairly nice and catchy song in the beginning and he's willing to take Squidward's place when Squidward is about to be dropped into the volcano. I also thought that the crazy dolphin guy was pretty funny. But my main problem with that episode comes from Squidward. His grumpiness goes WAY over the edge here. I really dislike Squidward in this episode and it just brings down an episode that would have been good had it not been for Squidward. I personally think he's more unlikable here than in Little Yellow Book and Whatever Happened To Spongebob? (WhoBob WhatPants). I don't think it's worthy of a Scumbob, it's a just a Meh. It's pretty close to Scumbob though because of Squidward. He deserves the torture in this episode and I realise I sound pretty horrible to think that.
All in all, I would give this entire mini-series a Meh, but still pretty close to being good. None of it is great or anything, just merely passable.