Understandable, during gen-con I had to keep reminding some of my opponents about their "shape change". Some times the level of intensity during a game can be over whelming.

A player at my venue has a habit of saying "I'm attacking X" and then rolling the dice immediately. Sometimes I remember to say "Wait, I have Shape Change!" but not all the time...

What makes my mental slip especially galling is that I'd designed a Quintessence team - Black Flash and The Spectre - and then somehow let my opponent Outwit me anyway.

I'm sorry but you rule lawyer'ing a bit and that's not fun at all. if he took another action then wanted to change i would say no way but the way you stated it I would have let him change it.

IMO

Ah Force Blast... my gf's Man of Steel got taken out by Force Blast in a game last Saturday... Not the way you'd expect Supes to drop, lol.

Pretty much what I like to call "Game Show Syndrome." You can sit on the couch watching Jeopardy, Wheel of Fortune, or whatever game show and rag on the contestants for getting the answer wrong or mentally buzzing in with the answer a split second faster than they actually did, but it's a completely different beastie when you're on the stage in front of the crowd, with the lights shining on your face... then you realize what's up for grabs here.

Mine was in an odd format.

Six figure team that fit into these catefories:

1 – Up to 25 Pts
2 – 26-50 Pts
3 – 51-100 Pts
4 – 101-150 Pts
5 – 151-200 Pts
6 – 201 Pts or more

You will begin the game with your lowest point figure on the map. When the dial turns for any reason, you will roll 1D6 and swap out the corresponding figure. If the corresponding figure has been eliminated you will bring in the next lowest figure.

So I was facing my opponents KC Flash when he damaged a figure of mine and I rolled and got to bring in Metron. In my mind I was quite happy as I thought to myself, "Excellent! The Anti-Flash piece! He can't hurt me and I will either hit him eventually or he will have to push to take damage!"

Then, almost immediately, he says "I outwit your imperv...hit, take 2."

I was all, "OK"

D'oh!!!!

Yeah, I'm not reading allll this. In general, if no other actions are completed (no dice rolled) I'm usually fine with changing Outwit or Perplex.

However, there is something to be said of "learning by mistakes." I always encourage noobs to think at least 1-2 actions ahead (and for those who want to become more advanced players - think 1-2 turns ahead). For veteran players when they try a take back or do an "after the fact" declaration, my response is something along the lines of "C'mon, how long have you been playing this game?" (jokingly).

As I believe has been mentioned, how declarations/take backs play out depends on game/round. If I have an unimportant game well in hand I'm not going to care about little things. If I'm in the final round and it's close, that may be another matter.

There are a number of factors that come into winning a game of HeroClix:
Team build
Map choice
Strategic and tactical plan
Error-free play
Luck

If team building skill and strategic/tactical thinking are roughly equal, the other factors become critical. Map choice can be significant, but between to fairly even players generally the player who has the better die rolls and who makes the fewest mistakes is going to win. Not making mistakes and capitalizing on your opponents' is fundamental to winning the game.
So the idea that the win only means something if your opponent plays error-free, or that you should allow him to retract tactical errors in the interest of sportsmanship, is ludicrous. He is responsible for his game, you are responsible for yours. To diminish George's win because it sprang from Allan's mistake, or to suggest that there is anything shameful or dishonorable in his expecting his opponent to play by the rules is absurd. People who don't get enjoyment from playing the game at that level should stick to Battles Royale or more casual events: they shouldn't play in major tournaments.
I'm also really tired of seeing people accuse those who play by the rules of taking the fun out of the game: the game is the rules, otherwise we're just playing army men with super hero figures. It isnt called rules lawyering, or being a dink: it's called playing HeroClix.

To the OP: I think it's already been covered that by the rules you're correct so no need to cover that again.
I'm a pretty casual player, usually willing to give my opponent the benefit of retracting an error because my games are usually just friendly games, bye rounds or they're teaching games for new players. Allowing an inexperienced player to back up a bad move while explaining why it was a mistake is reasonable if you're trying to teach them, and taking advantage of their lack of knowledge to crush a new player just discourages them from playing again.
But in the situation you describe, I'd say you're in the right. As I read it, this isn't an inexpreienced player making honest mistakes, it's a player with experience who's sloppy and counting on do-overs to get him out of his errors. Allowing the do-overs just encourages him to keep being sloppy.

This has been bugging me since I herd what happened at worlds. If this is the true course of events I think there was a missruling here.
The fantastic four rule book has this short paragraph about first round immunity.

First-round immunity. In the first round of the game,
characters belonging to a player can’t be targeted, knocked back, attacked,or damaged until the beginning of that player’s first turn. Further, no characters can be knocked back, attacked, or damaged by opposing characters during the first round as long as they occupy the square in their starting area where they were placed at the beginning of the game.


The crux of my argument deals with the bolded statements. The first statement says that your figs cannot be Targeted during the first round before your first turn. The second statement says that even after your first turn your figs can't be Knocked back, attacked, or damaged by opposing characters as long as they occupy the square in their starting area where they were placed at the beginning of the game. It does not however prevent an opposing character from targeting a character that has had its first turn but did not move. This is I believe a deliberate omition by the writers of the rule book to keep players from hiding in plain site from outwit and perplex and on very rare cases prob control. If there is a faq that over rules this then please let me know so we can change the ruling at our venue.

To restate my position a bit more clearly the first bolded statement describes what can be done to a character on the first round before his tun has been taken. The second bolded statement describes what can be done to a character during the first round but after the characters first turn should that character choose not to move or return to its starting position. Under this interpritation Metron would have been able to target Shazam/Black Adam with outwit because the Shazam/Black Adam had chose to do nothing during their first turn and outwit causes no knock back, is not considered an attack, and deals no damage which are the only things that can't be done Shazam/Black Adam at this point.

You're 100%...that that's how it was under the Fantastic Four rulebook.

Fortunately, that rulebook is not legal anymore.

Now, if you care to look at the current rulebook, page 6...
This is what first round immunity is now.