What does x damage mean?

Answer 1

At the bottom of each creature card, there are two numbers. The first is the power and the second is the toughness. Power is the amount the creature can deal and toughness is the amount they can take before they are sent to the graveyard. If a creature on your side attacks your opponent, and he has no creatures out, he takes the direct damage. This amount is taken from their life which is usually around 20. If you and you opponent have creatures out, they will face off. A 2/2 would destroy a 1/1 and the 1/1 would be sent to the graveyard. The opponent would not take any damage but would lose his creature. Trample is a static ability that allows the creature to run over the creature and hit your opponent. if a 6/6 with trample attacked a 4/2, it would deal 4 damage to the owner However, a 3/5 could fight a 4/4 the entire game.

There are also cards that directly damage players, for example Lightning Bolt deals 3 directly to a player or creature.

Answer 2

When a spell, say "Fireball" has X in its cost, upon casting you declare a value for X. That value becomes all instances of "X" on that card, both in the mana cost, and the effects.

For Fireball, you would say X to equal 5. So you would pay 5R, to deal 5 damage to your opponent.

Answer 3

X damage in Magic: the Gathering can be any number. The card will usually have an explanation for the X whether it be in the mana cost or how many creatures you have of a certain type.