Effects that need to determine an ability’s cost for any purpose use its base cost, ignoring any alterations to that base cost unless otherwise specified. Example: A card reads “When you play an activated ability with Energy cost [7] or more, you may exhaust me to ready up to 2 runes.” A gear has an activated ability that reads “[12], Banish this: Choose an opponent. Banish all units they control. This ability costs [1] less for each point the chosen opponent has.” The ability of the first card will trigger when the activated ability is played, even if the chosen opponent has 6 or more points. Example: An equipment has an ability that reads “Equip [4][A]. This ability costs [1] less for each occupied enemy battlefield.” If its controller plays a unit with Weaponmaster, the Weaponmaster trigger will refer to the cost including the alterations. This is because Weaponmaster specifies that it includes modifications to the cost.
§ 206.1 Core Rules PDF (officieel)
§ 206 Effects that need to determine a card’s cost for any purpose always use its printed or copied cost, even if that cost is increased, decreased, or ignored as the card is played. Example: Sky Splitter is a spell that costs [8] and says in part “This spell's Energy cost is reduced by the highest Might …
