Hi, I play the Pokemon online game, and I wanted to know what is in your opinion the strongest theme deck out there. Thanks.
This is not competitive. Strongest theme deck = strong top decking / all theme decks equally suck.
Just grab a Pangoro, Slyveon, Yveltal, sometimes Xerneas, or the BREAKpoint decks. Those are the ones I have the most knowledge of, although the AOR decks could also be interesting.
Pangoro is the most famous for being "the best theme deck" so if you play it you'll run into a lot of mirrors; and people play Slyveon or Xerneas to counter it a bit (but they're decent in themselves).
Overall though Dark Hammer can only be so good; I've played (and won) PTCGO tourneys with it but if your opponent is playing ANY other theme deck and topdecks nicely while you do not... gg. It's subject to dead draws like basically any other theme deck.
As a side note, I hope others share my enthusiasm with doubling theme decks xD
Dude... chill... we all know theme decks are not something you bring to big tournaments (except to troll). But we should be respectful of the question; one I think is valid, ESPECIALLY for new players who need decent cards to start (particularly trainers).
The theme deck format has a bit more luck involved than Standard of Expanded. No one theme deck is really any better than the other--at least it would seem that way. What Yo-yos said is to some extent true, or at the very least he has the right to say so. There's no need to be bothered by an observation, even if it was a little blunt. That doesn't mean, however, that he would be right to say that there's no point in discussing the topic at hand. While I'll agree it's not exactly a highly competitive subject, it does require some understanding and thinking about the game, and there are probably a few insights we can provide that would be helpful for the OP.
For example, I think that in such an inconsistent format, generally speaking the decks that will do the best are the ones that are low maintenance. Few Stage 2's, more Basics, lower attack costs, etc. I also think Weakness is a huge deal. Something that has an uncommon Weakness would be nice. There's my input.