I agree with the rules not addressing some aspects, just wasn't sure if there was something extra about 'tournament'.
I agree about debris markers and maps, they were just hypothetical to demonstrate why I disagreed about markers being game elements, though Robohobbit did much better research on that one than I did.

I've never seen or considered the aspect of removing your objects. Doesn't make 'logical' sense(real world), but of course that has no actual bearing on the rules of the game! I'll have to remember this from now on.
I guess where I have a problem understanding is, how is this non-functional. Other character's effects can change terrain and are permanent, and you don't have an issue with those. SC/Barrier also have no duration, just a trigger, that in this case is never triggered. What is broken? Worst case scenario, you box in one opponent's character, while no character remaining has the ability to destroy any of the markers. Well, that could happen with other 'allowable' effects, and it's also perfectly natural to end a game with 2 characters that have no capacity left to damage each other, so I don't see this as non-functional and needing an intent ruling. Obviously any other effects those markers may have had from their creator no longer exist, so they are just 'plain' terrain now. Maybe it would help me if I understood 'why' this was a problem that we had to rule to prevent?

Because its not something that is supposed to happen during the game. Maybe duration was a poor choice of words, but I was speaking in a general sense. Any effect that the game would normally end should be removed. Meaning effects with duarations, or in this case, an effect that places markers that has a built-n way to prevent that removal from being circumvented (since both powers specifically use "even if lost" in the trigger).

Point being, these are things that *should* happen, according to the normal rules of the game. The people writing the rules just didn't bother to make it functional for multiplayer.

And the things you described are definitely an issue. Its not about the fact that these conditions could happen in a game normally, its about the fact that these conditions are being allowed to perpetuate after they normally should have ended. If a player in a game is taking actions to cause these situations, that's fine. Its not fine when its an unintended side effect of poorly written rules that allow the effect to stay in place permanently once a player has been eliminated.

It would allow for some fairly shady stuff to happen, too. Yes, players can Barrier to box in a character that can't destroy the blocking. In a 2 player game, one player is using an action to shut down another piece. In multiplayer, one person could push his last character to death to Barrier another character in permanently, effectively eliminating that figure in a way that is not intended. A player could do this purely out of spite, to deny points or actions to other players, or strategically, to protect another players piece. None of those should be acceptable.

Even if a player is actively using Barrier in this way every turn, there's still at least the possibility of the opponent interacting in some way. Outwitting Barrier, damaging that character, using some kind of effect that prevents opposing characters from using it, etc. None of those things can do anything to affect this now permanent Barrier.

And to go back to the previous point about it being a "tournament procedure" issue, removing an eliminated player from a multiplayer game should fall under that general umbrella. Its less about game mechanics, and more about keeping things running smoothly. Also, when I say "tournament", I don't necessarily mean an event with multiple rounds. Multiplayer events almost never have more than one round. "Tournament" in this context just means any formally run event, like Battle Royales at a WKO, which should have a standardized way of doing things.

To give another example, one where it does actually use durations- Would you argue that this Outwit would last the rest of the game if the player has been eliminated? Slightly different, obviously (duration of Outwit vs. trigger to remove markers), but exactly the same principle.

Bottom line being, an effect that is supposed to end should not be able to continue effecting the game due to a loophole.

It would be best for the remaining players if, when a player is defeated, all game effects brought into play by pieces they had used in the game would immediately end.

Otherwise, shenanigans.

That would cause a ton of pieces to not work correctly.

Well, on the one hand, I really enjoy when I, or others, find such 'loopholes' that add an interesting twist to the game. If a player manages to pull off such a feat at the right time, in the right circumstance where it actually has strong affect on the outcome of the game, they deserve to enjoy it. And outside of 'unfairly teaming up' against opponents, it would be perfectly acceptable to use it strategically to 'deny points' and keep your point standing for the match. No difference between that and running away. Might be a jerk move in some instances, and I would usually avoid such things, but it is a game and the point is to make strategic moves in your advantage to win. And in those respects, I 'would' argue for Batman's perma-outwit!

However, on the other hand, in a 'tournament' setting, I can understand the need to be 'politically correct' with everything, and since it 'could' be abused in certain situations, they should all be equally prevented. We should keep a running list of these things for WizKids, maybe they would just 'adopt' your tournament guidelines!

This is pretty much exactly the whole point. 99% of the time, it won't actually matter, but if there's potential to abuse a loophole, it needs to be shut down.

And I get certain players enjoying finding loopholes in games. That's fine. But by their very nature, loopholes are unintended interactions. They're against the spirit of the game, and harmful when not addressed. Its one thing when something weird comes up in a game. Its quite another when someone intentionally tries to abuse a loophole for an unfair advantage in the game. This is exactly why we have that section in the tournament rules to cover loopholes, even going so far as to let Judges completely disallow abusive team builds.

Like I said, I'm fine with any ruling that actually ends effects that are intended to end, be it immediately, or when it would normally end (even though the second one requires a little more twisting of the rules on a technical level, despite being perfectly intuitive).

examples?

let's say my Ultron-5 has laid down a bunch of smoke cloud tokens and he's my last figure and he's defeated.

You want to leave those on the map until ... my "next turn"?

I'm not proposing removing things put down/ game effects created by other players.

Your original statement is much broader than you probably realized. "Game effects" covers a lot more than just SC/Barrier markers.

Well you said "all game effects", so that would stop game effects that are meant to last for the rest of the game as well. Basically, anything that's "until the end of the game" or other durations.

my bad, yes, I overreached with my prior response.

I agree with Lantern (although I might rule that the barrier hangs around to what would have been the players next turn - without much thought that seems like it would fit my personal instincts better).

There were days in the past where WizKids lacked alacrity when it came to some of these issues. SIF abuse comes to mind.

Making an Intent Ruling is something that you want to be very careful with. Sometimes intent rulings are not so obvious.

I distinctly remember one time at Worlds a player built a Thanos solo team stacked with lots of Feats including Protected. One of his opponents knocked the Protected off him scoring points and then Thanos started running away. His opponent allowed him to runaway assuming he would win on points. However, at the time there was a rule that said if no "character" was defeated on either side the team with the lower build won. The Thanos player was aware of the rule, his opponent only remembered the short-hand concept.

To be clear, I think that would be the preferred solution. Its just that the rules technically don't really allow for it as written. There would need to be some weird exception that allowed the defeated player to get another Beginning of Turn phase, during which all they were allowed to trigger were the effects to remove these markers, while also preventing other people from triggering anything.

I think most of us agree its intuitive what should happen, but its something of a nightmare on the technical side of things.

Which describes a lot of things in this game.

An Intent Ruling is by it's own nature outside of the rules. The rules technically don't allow for what is being ruled on intent, so I don't see that as being a binding issue. Just a simple statement like:
Might need tweaked some.

That is a lot of words and not simple. Let's go with:

"Effects with a turn duration expire normally when the defeated player's next turn would have occurred in the turn order."

This is not perfect but pretty sure there are solutions that would not be complete nightmares.