Giving double strike to a creature with first strike after it has already dealt combat damage in the first combat damage step will allow the creature to assign combat damage in the second combat damage step.
June 17, 2011 · Commander 2011
Giving double strike to a creature with first strike after it has already dealt combat damage
February 4, 2011 · Mirrodin Besieged
Giving double strike to a creature with first strike after it has already dealt combat damage in the first combat damage step will allow the creature to assign combat damage in the second combat damage step.
October 1, 2010 · Scars of Mirrodin
Giving double strike to a creature with first strike after it has already dealt combat damage
February 1, 2010 · Worldwake
Giving double strike to a creature with first strike after it has already dealt combat damage in the first combat damage step will allow the creature to assign combat damage in the second combat damage step.