Wanted to expand on my earlier feedback for Comment Club. :)
Least favorite: Overall, I felt it was quite easy. I didn't really feel like there was any danger of running out of blood. There are a lot of levels that have enough enemies to replenish any missing blood. Spamming the bat button basically ensures nothing can ever hit you, and if you do happen to descend on an enemy they'll die. I'm usually not a fan of time pressure in games, but adding more things that drain your blood as well as limiting the bat ability or adding some risk/reward would probably make it more engaging.
Most favorite: As I said previously it looks so great with such minimal assets. I love 1 bit styles and it's done so well in this game. The shadows look great. The music fits the overall feel of the game so well. The presentation is just well done all around.