When using the Cursed Shovel trainer card and you remove two cards from your opponent’s deck, if one of the discarded cards is a Mega Mewtwo EX, does it entitle me to take two prize cards?
The wording on Cursed Shovel says
If the Pokémon this card is attached to is Knocked Out by damage from an opponent’s attack, discard the top 2 cards of your opponent’s deck
Looking at The rules here for Pokémon-EX say
When one of your Pokémon-EX is Knocked Out, your opponent takes 2 Prize cards.
The appendix for 'knocked out' says
A Pokémon is Knocked Out if it has damage greater than or equal to its Hit Points. That Pokémon goes to the discard pile along with all cards attached to it. When one of your opponent’s Pokémon is Knocked Out, take one of your Prize card
So you would not be entitled to take two prize cards. You only take a prize card when you knock a Pokemon out. Cursed shovel places Pokemon in the discard pile, it is not the same as 'knocking out' and would not give a prize at all.