Happy Chance

[dannyl16]

my oppenent plays a blissey and attacks with happy chance
he grabs 3 :grass: from his discard and attaches them to blissey for a total of 60 damage

i told him the card text says "Before Doing Damage, you may search your discard pile for A basic energy card and attach it to blissey"

we got into a little argument and at the end i was a little confused and just let it go

can anyone please help me with the correct ruling please.

 

[PokePop]

Yes, you are correct. It says "a" basic energy card.
Not sure on what basis your opponent thought "a" means "as many as you want".
It doesn't.
Just one.