I bought this immediately after seeing it. Although I'd never played Crypt of the NecroDancer, I've been keeping an eye on it and also really like the soundtrack in it's own right. In what I think is a first for Nintendo, they've licensed or collaborated with Brace Yourself Games to bring you a crossover of Crypt & A Link to the Past. The music is amazing, it has satisfying combat and it's a pretty faithful crossover of the original. It had a bit of a learning curve, but within half an hour or so I was really into the music, moving in time to the enemies and making my way through the map. It's unique and totally worth playing if you're into Zelda or enjoy games with great music.
The standout fantastic thing about this game is the soundtrack, especially if you're familiar with Zelda's music. It doesn't just work with the mechanic; it's actually great to listen to in it's own right. They've managed to keep the original themes and make them fit in with Crypt's perfect-sync combat mechanic. It was nice to see a mix of enemies from all the Zelda games that I haven't seen for a while too; Moblins, Poe, Deku Scrubs, Floormasters & Keese (and lots more). Each enemy has a predictable pattern, and the key to defeating them is knowing where they're going to move next (except when they put them shoulder to shoulder in a room with one exit, then you can just stand there and stab while they all walk into you). Where it gets interesting here is a whole screen full of enemies and how you then have to watch for which is the next threat. Because it all moves to the beat, you also only get a short time between beats to make your next decision. If this is really putting you off, you can also play the game with the music sync turned off, so enemies only move when you do.
The story is that Cadence from Crypt of the NecroDancer falls through a portal and lands in Hyrule. Octavo, the resident bad guy is trying to defeat Ganon using magic instruments (doesn't seem that bad really), so you need to beat the crap out of his instruments so YOU can defeat Ganon instead. You can play as Link or Zelda, and you unlock Cadence in the last hour or so (I didn't play as her at all). Oh and it can also be played co-op if you're that way inclined.
I never bought Crypt of the NecroDancer because it was touted as hardcore difficulty, which I rarely like. I noticed it was on an 'E3 Sale' though so I picked it up for €4 which is worth it - I wanted to see how much from Crypt had been ported over. I don't think I'll play it that much though, it's a great concept but it already feels dated even though it's pixel graphics - perhaps it's just quite low fidelity. I found the Zelda version much more polished and enjoyable. Crypt is a roguelike where you get incremental upgrades each time you die in the form of diamonds as currency. They ported that in to this one, so when you die you can use diamonds to purchase some limited-use items like torches or bombs. I don't think it really fits here that well though, as I never really needed the items and ended up with hundreds of spare diamonds by the end of the game.
They've included LOTS of items from Zelda - even the bottles to keep health potions in. There's the boomerang & magic boomerang, shield, hookshot, longshot, arrows (ice & fire), power glove etc etc. That's cool, but to be honest I found that I practically never used them; I just didn't have the need with the way the combat worked. There are different weapons to find, and fairly early on I found a spear that reached two tiles, did two damage and I used that for the entire game.
My only real criticism is that it was too short and a little easy. A Link to the Past has a whole new map open up once you first defeat The Wizard. However, in this game there are the first four bosses from the temples, then the last boss fight and that's kind of it. I understand why they didn't include the shadow world, because the original is a lot more about exploration which would be more difficult to port in to this combat focused version, but it does feel like half the game is missing. In terms of difficulty - I killed all of the bosses on my first attempt including the two last bosses. It's damn fun though.
I don't know whether it will stay online, but for now there's a YouTube link to the 5 hour soundtrack here: https://www.youtube.com/watch?v=5AXxJbctW6U.