Battle cry

Battle cry is a triggered ability first introduced in Mirrodin Besieged and gives a +1/+0 bonus to each other attacking creature, thus being more or less an inversion of Exalted.

History
After Mirrodin Besieged, Battle cry made appearances in Unstable and Modern Horizons. The mechanic has no creative difficulties, with its medium Storm Scale score largely due to its forgettability.

Battle Cry has to date appeared on nine cards, seven of which originally carried the Mirran watermark.

Rulings

 * The +1/+0 bonus applies to each other attacking creature, but not to the creature with battle cry itself.
 * The +1/+0 bonus remains until the end of the turn, even if the creature with battle cry leaves the battlefield or stops being an attacking creature.
 * If a creature with battle cry attacks more than once in a turn (due to an additional combat phase being created), its battle cry ability will trigger each time. The results are cumulative.
 * In Two-Headed Giant and other multiplayer variants where players share a turn, attacking creatures controlled by a teammate also receive the +1/+0 bonus.

Trivia

 * Battle Cry was featured as rules card 1 of 5 in the Mirrodin Besieged set.
 * Battle Cry was considered as the Boros mechanic for Guilds of Ravnica.