Well, well, well. What an achievement. The twitch platforming of the classic NES side-scrollers merged with a narrative and structure reminiscent of the Metal Gear Solid series (Ice Quest, the game-within-a-game, must certainly a nod to the Kojima's sense of humour).
Excellent animation, voice acting, music and gameplay. The atmosphere was mysterious, and the boss battles epic. You really do have to spend some time learning their patterns and behaviours. To me, this is the mark of a good, challenging boss fight.
And what an ending! Bring on the sequel, I say! I don't often write reviews. But this was spectacular.