BUG: Mew Genome hacking Vs Palkia Dimensional Storm.

When i use mew's attack "Genome Hacking" on Palkia to copy the "Dimensional storm" of Palkia, Mew copy every effect of the attack:

-I deal 150 dmg to my opponent
-Every benched pokemon take -20 HP...

BUT mew doesn't discard 3 energy ! ! ! It should since it doesn't specify a type of energy.
Mew should loose 3 energy to use this attack if i understand it correctly.

I let this message here, to discuss about it if you think mew should discard 3 energy, or if you think there is a hidden rule that i miss here.