417.6.b. If a game effect does specify a source, then that source is what is considered the origin of the Damage for this Deal action. 417.6.b.1. Units and Spells can be the source of Damage for Deal actions. 417.6.b.2. Abilities can be the source of Damage for Deal actions. 417.6.b.2.a. When an Ability is the source of Damage for a Deal action, it is in addition to the Spell or Unit that created that Ability. Example: Iron Ballista is a gear that says “[E]: Deal 2 to a unit at a battlefield.” This damage is dealt both by a gear and by an ability. 417.6.b.3. When a spell or ability specifies a Unit as the source of the Damage for the Deal action, it is not in addition to the spell or ability that specified it. Example: Challenge is a spell that reads “Choose a friendly unit and an enemy unit. They deal damage equal to their Mights to each other.” The damage that Challenge causes to be dealt is dealt by the chosen units, not by Challenge.