Game's out. It has a huge variety of very creative platforming setpieces, drawing from a wide range of influences. The quality of the boss fights is rather uneven (and WTF is up with Crazy Quixote/Tin Man), but overall it's a very enjoyable and authentic-feeling tribute project. Difficulty is at about a Chou Makaimura level, although you can take three hits instead of two, and health items are fairly common. 1ups are also handed out in certain chests and in the bonus stages. The best weapon for the majority of situations seems to be the axe.
There are these blue gem items hidden at the end of difficult optional paths. I assume the way to get the best ending is to find them all. Some of them require lugging around keys for part of a stage without picking up another item or dying, like in Dracula X: Chi no Rondo.
The Gradius moai heads have a prominent role in stages 3 and 5. It's neat to see them, but I think the designer could have been a little less obvious in his references. I also noticed that a few sound effects were swiped from Makaimura, or recycled from Hydorah.
Speaking of Hydorah, the game recently got an update that fixed the infinite boss milking, bumped up the difficulty and added more screen options.
Hohe Türme ragen senkrecht und dicht gedrängt gen Himmel
Stahl, Qualm und rauchende Schornsteine
Eine Zukunftgesellschaft im Zerfall
Vögel in der Finsternis