EnchantEnchant is a static ability, written “Enchant [object or player].” The enchant ability restricts what an Aura spell can target and what an Aura can enchant.
For more information about Auras, see rule 303, “Enchantments.”
If an Aura has multiple instances of enchant, all of them apply. The Aura’s target must follow the restrictions from all the instances of enchant. The Aura can enchant only objects or players that match all of its enchant abilities.
Auras that can enchant a player can target and be attached to players. Such Auras can’t target permanents and can’t be attached to permanents. (CR 702.5) creature
When this Aura enters, put a +1/+1
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on enchanted creature.
Enchanted creature has "Whenever this creature attacks,
doubleDoubling a creature’s power and/or toughness creates a continuous effect. This effect modifies that creature’s power and/or toughness but doesn’t set those characteristics to a specific value. See rule 613.4c.
To double a creature’s power, that creature gets +X/+0, where X is that creature’s power as the spell or ability that doubles its power resolves. Similarly, an effect that doubles a creature’s toughness gives it +0/+X, where X is that creature’s toughness. Doubling a creature’s power and toughness gives it +X/+Y, where X is its power and Y is its toughness.
If a creature’s power is less than 0 when it’s doubled, doubling that creature’s power instead means that the creature gets -X/-0, where X is the difference between 0 and its power. Similarly, if its toughness is less than 0 when doubled, it gets -0/-X. If one characteristic’s value is negative but the other isn’t when both are doubled, it gets -X/+Y or +X/-Y, as appropriate.
To double a player’s life total, the player gains or loses an amount of life such that their new life total is twice its current value.
To double the number of a kind of counters on a player or permanent, give that player or permanent as many of those counters as that player or permanent already has.
To double the amount of a type of mana in a player’s mana pool, that player adds an amount of mana of that type equal to the amount they already have.
To double an amount of damage a source would deal, that source instead deals twice that much damage. This is a replacement effect. (CR 701.10) the number of +1/+1
countersTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on it. Then if it has power 10 or greater, draw a card."