If I lost zone a magnezone lv X and use his attack which specifically says I have to discard a number of energies attached to Magnezone, would I have to discard them from mew prime. Thank you.
Basically what the above said, the self reference is applied to the Pokemon for damaging effect, but does not carry over for cards such as Mareep HS who count for how many "Mareep" you have in play. If Mew copied Mareep's attack it would still be looking for Mareeps.