Unlike many other Shoot Em Ups of its time, the game has you pilot a Humongous Mecha that fires out Rocket Punches for its weapon. Along the way, you can also pick up a gun for your mecha, and eventually, larger modules that boost your firepower even further. Taking damage will downgrade your mecha's form (or lose its upgrade module if it has one) to a standard ship, which will be destroyed on the next hit, although you can upgrade your ship back up to mecha form (it takes one powerup to upgrade to a larger, slightly more powerful ship, and one more to upgrade back to mecha form).
If you are in upgraded ship form or higher, you can split your mecha/ship up (up to 3 times, unless you get an upgrade) into separate parts. In ship or mecha form, this reduces your hitbox and turns your non-main parts into Attack Drones. In upgraded mecha form, this grants an alternate fire form.
Dangar is a pretty neat shooter, especially for its time, if you can get past some of its quirks as an 80's shooter (Checkpoints instead of respawning where you died, the fact that you need to stay alive long enough to get the upgrades, lack of bullets in contrast to more modern shmups).
Dangar - UFO Robo contains examples of the following:
- Combining Mecha: Three jets forming the robot.
- Eldritch Location/Evil Is Visceral: At set points during the stages, you'll find black portals that take you to one of many alternate dimensions, where you must traverse various alien horrors and fight a boss at the end to escape.
- Mecha Expansion Pack: In game power ups you receive a gun and a giant UFO equipped with Laser Beams, Fire Shots or Spread Shot.
- Invincible Minor Minion: The flashing square blocks will absorb your shots, and can't be destroyed.
- Nintendo Hard
- Shout-Out: The title recalls another UFO Robo.
- Rocket Punch: Your mecha form's main weapon.
- Unstable Equilibrium: Avoid getting hit and pick up the upgrades along the way and you'll have a near-unstoppable mecha that can chew through enemies with trivial effort. If you get hit and die a lot, don't expect to see any of the mecha's forms.