What is the general rule of how to handle mistakes in play. Here is a couple scenarios that happened yesterday:

I attempted to play Frozen Solid (Attach to non-limited location cost 3 or less and treat that location as if it has no text) on The Arbor (cost 4 limited +3 gold). This is an illegal target, what should happen? Does the card get discarded? Does it return to my hand? I currently had The Iron Throne in play (cost 2, +8 str during dominance, +1 reserve). Would I be forced to target my own card since it was the only legal location in play?

In the same game my opponent attempted to use Support of the People (play only when you win a power challenge by 5 or more. Search for a location with cost 3 or less and put it into play) after winning a military challenge by 5 or more. What happens in this case? Should it be discarded or returned to his hand?

We're still learning how to play, but we're trying to play by proper rules in order to correct our misplays. We also play 90% melee so just having misplays disqualify an opponent isn't really an option.

Thanks!

The only official stance on misplays is, "The players should agree on the best way to 'fix' the game state."

- So, whatever you and your opponents agree is the best way to handle each of those play mistakes/scenarios is the correct way to handle it.

- In a tournament game, if the players cannot agree, they will call a judge over, who will make a decision on how to "fix" the game state, and the players will be stuck with it.

Traditionally, if someone messes up the play restrictions and/or triggering conditions (as in the scenarios you describe), and this is discovered right away, players usually just back-up and treat the situation as if the card hadn't been played, returning it to the player's hand - although their opponents know what they've got in hand now.