The dynamic objective switch in a shmup works a lot better than expected. I expected it to be jarring, but the transition is really fluid. However, the spawning behaviour makes avoiding the mobs difficult or impossible if they spawn next to you.
The sound design is really good, expressive and communicative music and clips that help relate what actions are required by the player. The audio balance could use some work, the levels are too loud for many of the clips and the music. We noticed the sneaky HL head crab.
Visually it's very striking and unique, the gritty effects really sell the DOOM vibe!