From the original compendium: Q. If Neo3 Kingdra uses Genetic Memory to copy Fossil Seadra's Water Gun attack, how does that work as far as adding damage to the attack? (i.e., do you subtract out the Genetic Memory cost before determining whether you have enough energy to use the other attack?) A. Just as it states on the card. If you use one Water to pay for Genetic Memory and you have 3 other Water Energy attached to Kingdra, you will add 20 damage (because that is where it maxes out at) to the Water Gun attack. The 1 water is paying the Genetic Memory's attack cost which is taking the place of the Water Gun's attack cost. That 1 water would NOT count as an extra. (Jan 24, 2002 WotC Chat, Q26 & Q85) One attack cost replaces the other.