Uncontrollable Anger

Enchantment - Aura, 2RR (4)
Flash (You may cast this spell any time you could cast an instant.)
Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)
Enchanted creature gets +2/+2 and attacks each turn if able.¹
[A barbarian's heart pounds with the fury of a prisoner, threatening at any moment to break the bars of its cage.]
Illus. Kev Walker

Gatherer Card Rulings [Nov 2009]

• 8/1/2008: A creature required to attack or block if able in a given turn only has to do so during the first combat phase that turn in which it's able. Basically, each combat phase in that turn, you ask "did this creature attack/block this turn?" and "can this creature attack/block this phase?" If the answers are "no" and "yes" respectively, then it must attack or block as required. This is important if a turn somehow gains extra combat phases.

Format Legality	Legal in Vintage, Legacy, Extended Banned in Standard
Printings (2/17)	Tenth Edition (Common) Champions of Kamigawa (Common)