what is commander/casual/modern/standard
I'm lost,
I only play MTG with my friends and family with a mixed deck of 1990s through to 2018 cards, so I'm not sure
Casual is just playing for fun with nothing at stake. Playing with friends and familiy for fun is playing Casual.
Modern and Standard are Constructed formats. In a Constructed format you build your deck in advance of the event, and you are restricted in your card choices. What you are allowed to use depends on the format. In Modern all cards printed in regular sets since 8th edition, with the exception of those on the bannned list, are allowed. In Standard, only cards printed in the last 2 years are allowed. So Standard card legality changes regularly, new cards come in every few month, older cards go out. If a card is printed in a legal set, all printings of that card, no matter from when or where, are legal.
Commander is a special format, formerly known as EDH (Elder Dragon Highlander), an officially adopted format based on the player designed EDH. It's usually played as FFA Multiplayer (Free-For-All, =you can attack everybody).
Your deck must have exactly 100 cards, one of which is your commander. The commander must be a legendary creature (or one of the five planeswalkers that specifically state that they can be a commander). You can have only one copy of any nonbasic card in the deck (hence the term "highlander", using the motto "There can only be one" from the Highlander movie). Furthermore, the commander dictates what colors the cards in your deck can have. The format uses the concept of color identity for this. A card's color identity is all the colors of the mana symbols in its mana cost, plus all the colors in the mana symbols in its text box (except those in reminder text), plus any special color indicators. All the cards in your deck can only have color identities that are a subset of your commander's color identity. (No color and the full scope of your commander's colors are ok.)
The commander starts in the command zone and can be played from there. It can return there when it would leave the battlefield, if you don't want it to go to the zone it's sent to. Each additional playing of the commander from the command zone cost an extra 2 more. This increasing cost is known as "commander tax". Combat damage dealt to a player by a commander is "Commander damage". A player who has been dealt 21+ commander damage from the same commander over the course of the game loses, even if he still has a million life.
I'm lost,
I only play MTG with my friends and family with a mixed deck of 1990s through to 2018 cards, so I'm not sure
Modern and Standard are Constructed formats. In a Constructed format you build your deck in advance of the event, and you are restricted in your card choices. What you are allowed to use depends on the format. In Modern all cards printed in regular sets since 8th edition, with the exception of those on the bannned list, are allowed. In Standard, only cards printed in the last 2 years are allowed. So Standard card legality changes regularly, new cards come in every few month, older cards go out. If a card is printed in a legal set, all printings of that card, no matter from when or where, are legal.
Commander is a special format, formerly known as EDH (Elder Dragon Highlander), an officially adopted format based on the player designed EDH. It's usually played as FFA Multiplayer (Free-For-All, =you can attack everybody).
Your deck must have exactly 100 cards, one of which is your commander. The commander must be a legendary creature (or one of the five planeswalkers that specifically state that they can be a commander). You can have only one copy of any nonbasic card in the deck (hence the term "highlander", using the motto "There can only be one" from the Highlander movie). Furthermore, the commander dictates what colors the cards in your deck can have. The format uses the concept of color identity for this. A card's color identity is all the colors of the mana symbols in its mana cost, plus all the colors in the mana symbols in its text box (except those in reminder text), plus any special color indicators. All the cards in your deck can only have color identities that are a subset of your commander's color identity. (No color and the full scope of your commander's colors are ok.)
The commander starts in the command zone and can be played from there. It can return there when it would leave the battlefield, if you don't want it to go to the zone it's sent to. Each additional playing of the commander from the command zone cost an extra 2 more. This increasing cost is known as "commander tax". Combat damage dealt to a player by a commander is "Commander damage". A player who has been dealt 21+ commander damage from the same commander over the course of the game loses, even if he still has a million life.
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