Attack if Able

Attack if Able is a demerit effect in which a creature is forced to attack if able.

Details

It commonly refers to the ability that forces a creature to attack each turn "if able". This "if able" condition requires the creature to not have summoning sickness and not to have been put into the battle zone during that turn, or being prevented from attacking by other effects such as Nariel, the Oracle.

This also sometimes calls a creature with this ability a "Mandatory Attacker". You aren't allowed to use a Tap Ability if they had one.

It is a demerit often found on creatures in the Fire Civilization, while the Darkness Civilization often grants the forced ability to attack to your opponent's creatures, and the Nature Civilization forcing them to attack your creatures.

This creature attacks each turn if able

Creatures with this ability must attack each turn unless they can't attack by summoning sickness, etc.

This creature attacks twice each turn if able

Essentially the same as above. However, the creature untaps itself and must attack twice.

Each of your other creatures must attack if able

Creatures with this ability force your other creatures to attack.

This excludes creatures that can't attack normally (such as Can't Attack) or that have summoning sickness. Creatures that can't attack the opponent are still only able to attack if your opponent has a tapped creature.

Even if a creature with this ability leaves the battle zone, the effect remains. (see Continuous Effect).

All your opponent's creatures attack if able

These cards give your opponents creatures the demerit of forcing them to attack, often leading to self-destruction.

Slime Veil, Forced Frenzy

Your opponents creatures will attack ~ if able

This ability forces your opponent's creature to attack, as well as changing their attack target.

However, if the attack target is untapped, it can't be attacked.

All creatures attack if able

All creatures (both yours and your opponents) must attack. It is a static ability that applies while the creature is in the battle zone.

Your opponents attacking creatures attack ~ if able

This creature limits the attack target of what your opponent attacks.

The text for this effect has changed occasionally. It is similar to the Guardman keyword.

Rules

"Attacks if Able" and "Can't Attack"

• Occasionally, it is believed that if you must attack "If able", then you have to attack, even if the creature is limited to.

"If able" only refers to the condition of already being able to attack (i.e. not having summoning sickness) or not being prevented from attack.

"Can't Attack" and "Attack if Able"

• If "attacks if able" (forced) and "Can't attack" (prohibited) effects are both applied at the same time, the prohibition takes precedence. Even if you cast Forced Frenzy while Nariel, the Oracle was in the battle zone, creatures that have more than 3000 power can't attack.

"Attack Target"

• Notice that "your opponent's creatures attack ~ if able" is written on an ability such as Forbidding Totem. This doesn't force your opponent to attack, only limiting what they attack. They are unable to attack the player or any non-Mystery Totem creature.

It differs from the effect that forces your opponent's creatures to attack, as well as creatures if able such as Heavy, Dragon God.

Other

• A card such as Storium, Light Ray Doll can be used to prevent any of your other creatures from attacking.
• This type of ability is affected even by creatures that have a Diamond State. The Diamond State would force any creatures that were previously unable to attack (in most cases, even if they had summoning sickness) to attack.