This is probably the first time in a couple of years that a NG game managed to make me come back to play it a second time. I enjoyed it quite a bit, although there were a few gripes I had with some aspects of it.
For starters, the orange teleport-mcguffins seem to have the ability to teleport inside of you, which I found a bit cheesy. They also teleported into walls occasionally, but this was not much of a problem because they then teleported out.
The pillar hitboxes seem a bit off. In the treasure/emperor tomb room in particular, it seemed like you could move behind on the top of the room, but it ended up getting me cornered between two of the miniboss slime things.
The gameplay got much easier after about level 15 or so when the rapid fire had no cooldown. To be honest, though, I did enjoy that it just allowed you to mow things down rather than try to restrict you, even if it did become dull after a while.
The replayability is great, especially considering that this is a free NG game (can't call it a flash because it uses webGL, not complaining though, these run much better,) although it did get somewhat monotonous after about the level 35-ish mark.
The lack of content is completely understandable considering the early state this game is in, and the fact that it was able to keep me coming back multiple times with the limited content provided just makes me imagine what this game is going to be like in a further state of development.
All in all, keep up the good work, and I can't wait to see what this game will be in the future.