I have two edh questions
1 I {mystifying maze} an opponents commander. Does it return to the command zone, or does it do the cards effect and stay in exile.
2 we are already discussing this in a different thread, but that is going no where. Can I have 60 odd {relentless rats} in a commander deck. Some people say, the rules say otherwise. Some people say the card overrides that rule. Some people say the people who design magic say its ok. What wins?
The EDH Rules Committee has stated it's okay. http://forum.dragonhighlander.net/EDH_Forum/viewtopic.php?f=2&t=127&start=17
Also in almost every case, rules on the card trump rules in the game unless there is a specific ruling, which I have not found.
Ruling 12/1/2004-{Relentless Rats}'s last ability overrides the normal limit of four of an individual card in a Constructed deck.
Whether it also refers to commander, I don't know but I would assume so.
Relentless rats are legal to have multiple copies in EDH. So are {Shadowborn Apostle}s now that they exist. Card rulings printed on a card about number-in-deck legality supersedes format.
As for exiling with mystifying maze, it would be that commander's controller who chooses what happens. Since you may -choose- to send him to the C-Zone upon exile, he gets that choice. If he returns him to the C-Zone, he will stay there and not return when the maze's effect ends (as he is no longer in exile to return from). He will suffer the normal +2 casting cost to recast penalty. If he chooses to leave the commander in exile from the maze, it will return from the end of the Maze's effect as normal.