But does it get a bike too?

Oh man this is brilliant. Make it its own post please, don't bury it here in the comments!
The paracausal tarrasque seems like a genuinely interesting concept. Gives me False Hydra vibes
Okay, this one I'm sending to my DM.
Cool list. #10 reminds me of Vash the Stampede

I had used one as the BBEG in a campaign I ran once. It was strictly for a their tier 4 climax and they had multiple side quests to help get some advantages like overcoming the spell resistance or temporarily stoping the health Regen. However, I also gave the Terrasque a ranged attack, and a few extra abilities so the players couldn't metagame and fly and kite.

And they had to figure out a way to trap the monster in a canyon.

Even still I dropped every PC to 0 health at least once in that encounter before they won. A real nail bitter.

It was one of the top five boss fights I ever was a part of on either side of the screen.

Nice! I had a 3.5 campaign I was running once where one of the major plot points was going to be a guy who was cloning Tarrasques and experimenting on them, but the game fizzled out because of me falling down on the job.
- Woah cool idea!

I had to look up what a tarrasque was. Good God, what a can of fuck you.

as far as I know they were nerfed for the 5th edition. It's still a huge sack of health but AFAIK you can stay out of range by just flying over its head. Lore-wise, it's a walking natural disaster that destroys anything that enters its maw, even magical artifacts.
- I think that's largely a consequence of the 5e design in general. It doesn't leave a lot of room, natively, for exciting challenges from its monsters. You've got to go to third parties, like Colville's "action-oriented monsters", or other systems like PF2, to get that.
- This is because WotC designs for mass appeal, so their monsters need to be fair challenge even for an underoptimized group. Which makes them pathetically weak if you're playing with anyone else.
  
  Also, because playtesters at Wizards don't use any magic items for some reason

Player cancelling aren't that of a big deal comparing to GM cancelling. In the first case you keep playing while shit talking about Bob, in the other, you have to change your plan for the evening

A few of my friends are DMs and pretty much all of them (myself, a DM, included) pretty much just cancel the session if a player can't show.
- That seems unfair to the players who were ready and excited to play. If i set aside 4 hours to drive to a friend's house and play games, and im told it's canceled because 1 person said they can't show up, I'm gonna be pissed.
- This is making planning ever more complicated, I try to have 4 or 5 player, so the game can run with 1 or even two player not showing. Sure if someone just don't show on a regular basis, I'll re open her place to a new player. But people are abroad for work, have to deal with their kids, or have a peak of work, they let us know, and we find an in game reason for their character so not be available and the game runs fine.
  
  Even when the GM miss, we all have ready to play one shots lying on our computers, so not that of a big deal
- I tried to push for more practical approach to playing without a single player, but both in my D&D and in my Blades in the Dark groups, players just feel...uncomfortable with the idea and don't want to play if all players aren't there. I once proposed a system where we could play in smaller groups to accomodate one player's schedule not matching others...and upon realizing they wouldn't be playing in full squad in this sytem, that player just quit the campaign.
- We have the policy that we play as long as no more than one player cancels and their character is considered to never have existed for that session (important story items are of course transferred to a present character). Works quite well.
If all players cancel except GM, then does the GM continue the game and shit talk to themselves about the players all night?
- Nope. I would never, ever do a thing like that. I've certainly never sat at my computer drinking beers and complaining about people changing plans at the last second.
- They make a variety of solo RPGs, these days.
  
  Shit talk your players while playing your own damn game, with blackjack and hookers.

if that's the case for the campaign I'm currently a player in, the fight will have -7 tarrasques

Everyone gets their own Tarrasque Companion with some extras to spare

I was going to send this to my DM, but then I remembered that he would absolutely do it.

Someone please AI generate a Tarrasque riding a tiny bicycle.