''Battle Squadron: The Destruction of the Barrax Empire'' casts the player (or players, thanks to the two-player co-op mode) in a role of a pilot (or pilots) sent to rescue two human commanders held captive by the evil [[TheEmpire Barrax Empire]]. Data indicates that they are held on the planet Terrainia, which is predictably full of enemies... literally since it's apparently hollow inside.

The plot is obviously simple. But that's okay, since it's just an excuse to put the player through four completely different levels of total mayhem.

Released in 1989 for UsefulNotes/{{Amiga}} and in 1990 for UsefulNotes/SegaGenesis, Battle Squadron is a [[ShootEmUp Shoot'em Up]] that features some incredibly beautiful and advanced graphics for its time. Explosions, bullets, spaceships, scenery, everything is hand-drawn and carefully animated, the sound effects and the background music are also very memorable. Thanks to some creative coding, the authors even managed to include a unique "Predator" invisibility effect for some of its enemies. Despite its relatively slow - although adjustable to a degree, thanks to a hidden menu - pace it remains very much [[NintendoHard Nintendo Hard]], like many shooters of the era. Later received a somewhat inferior port to UsefulNotes/SegaGenesis and another, improved one, to Android and iOS.

!!Contains examples of the following tropes:

* AcePilot - two unnamed pilots in tiny "Mark 2 Cruisers" sent to the alien empire's central weapon production facility featuring some never before seen biological and mechanical weapons? True to the genre, they ''completely wreck the place''.
* BulletHell - starts of relatively easy, but ramps up the bullets quickly. This can even be further tweaked via the hidden menu.
* EndlessGame - after you beat the final boss, you're treated to the ending sequence, credits roll... and then you're back at square one, ready for another go. Explained as "[[HandWave the whole planet changing shape]]".
* EverythingTryingToKillYou - even your sources of powerups will shoot at you or try to ram you.
* HollowWorld - with three separate "inner cores" full of things to destroy, accessed via marked entry points on a wrapping outer layer, Terrainia definitely qualifies.
* HubLevel - the initial, relatively normal stage, which wraps around, reviving the enemies in the process.
* LevelGrinding - somewhat unusual for a [[ShootEmUp Shoot 'em Up]], you can stay on the hub level and power up your chosen weapon until you feel you're ready. Given the [[NintendoHard Nintendo Hard]] nature of the cores, it's probably well advised.
* OneHitPointWonder - the player's ship.
* OrganicTechnology - the inner cores are full of... things, as well as regular mechanical enemies.
* SmartBomb - the Nova Missile, notably somewhat difficult to perform... unless you're using a mouse.
* UpdatedRerelease - recently got one, for iOS and Android