Kingdra/double dragon energy issue

[rhyhorn trainer]

Ok, it's been a while since I have been on the forums, but I need to make sure that I'm doing a combo right.

I built a deck around the Half art kingdra from primal clash and just recently i added 4 double Dragon energy and I am being told that I can not do 2 things and need to confirm it from someone wiser than me.

1st, when using the alpha growth ability on kingdra, am I allowed to attach a double Dragon energy as well as a basic energy or even have both energy's be double Dragon energy?

2nd, when using kingdra's "Dragon blast" it states that I must discard a water energy and an electric energy, am I able to just discard the double Dragon energy to pay for this cost?

 

[Tagrineth]

You can absolutely Alpha Growth with a DDE. It just says "Whenever you attach an energy card you can attach 2", it doesn't specify basic energy.

Also since Dragon Blast says to discard Energy, not Energy Cards, you can absolutely discard 1 DDE and meet the discard requirement.

 

[rhyhorn trainer]

I thought as much but I had a player tell me that you couldn't discard for the energy cost because it's not providing water and electric but all energy.

and while I have you folks here, is this a legal turn,

T1 horsea active, attach water energy, attach muscle band
T2 evosoda horsea into seadra, wally into kingdra, Dde and a electric energy?

 

[tutti]

It is providing all Energy. Including water and electric. The attack doesn't say "discard an Energy that is only a :water: Energy [...]".

As for that order of events, I don't see a problem. T1 is trivially legal; T2 consists of 1. Evosoda on a pokémon you can legally play it on, 2. Wally on a pokémon that was just put into play (which Wally allows), 3. Energy attachment and using α Growth for a second Energy.