EDH

[Mprecilio@yahoo.com]

I just started play EDH and my friend told me 100 card deck that is the color of the legendary creature you chose. And he also said that you could have only one of each card, no duplicates, ect.

Is that all correct, even the thing about only one of each card???

[Keyeto]

In EDH, you have a 100 card deck, including your general (a legendary creature of your choice). The only copies of cards you can have are basic lands; otherwise you are restricted to 1. The cards in your deck can only be of a color that is the same as your general's color identity (mana cost and any colored symbols in the text box) and cannot have any color in its casting cost or text box outside of those colors. Hybrid cards and double faced cards count all their colors for color identity, not just one (or one side). 

[Spikepit]

Furthermore, any mana that does reach your mana pool that is not of your Commander's colour becomes colourless. If you are rocking a sweet EDHRDW and you {Traitorous Instinct} a {Llanowar Elves}, his ability will only make colourless, however, he stays green! One more little insight is if you have a mono black deck, you cast {Tatsumasa, the Dragon's Fang}, then activate its ability, the Dragon is blue. Loop holes of Commander can be confusing until you pay attention to precise wordin of the cards. 😬