''Zanac'' has some things that are subjective:

* DemonicSpiders
** Round Cores in the original, when they're fully open. They release projectiles which spin around, soak up quite a few damage and can overwhelm the player.
** Also, for normal aerial enemies, purple Lusters which fly around with a wise arc and that means usually firing its projectiles behind the player.
** Jack the DynamicDifficulty high enough and you get these annoying blue enemies that line up with you and shoot out a constant stream of missiles. Flying above them will NOT help because they can fire upwards too.
* GameBreaker: Weapon 7. Fired fast, could move left and right at a limited angle, and could go through enemies. Very powerful, but is also a bit of a rarity.
** The [[GuestFighter FC-Custom]] in ''Neo''. It's basically an {{Homage}} to the original ''Zanac'' fighter that is unlocked through either a code or having a save file of the original Zanac game, and it plays exactly like the original down to the weapons degradation system, so no [[SuperMode blast mode]] or charge shots. However, all of its subweapons can destroy enemy shots, and this is a ship that, with weapon 7, can rip the crap out of anything. For reference, the regular ''Neo'' ships can only destroy enemy shots through sacrificing offense for defense, something that ramps up the DynamicDifficulty. Oh, and it benefits from the [[ExtraLife Landers]], having an insane rate of fire if exploited right.
* GoddamnedBats - Although many of the enemies qualify, T-Cells, which appear in Areas 8 and 11 in the original game, are perhaps the best examples. They cannot be killed with anything that doesn't clear the screen, they block shots completely and have to be destroyed [[CollisionDamage by bumping into them]].
* GoddamnedBoss - Capital ships in the original game since almost all projectiles bounce off of it (although still damaging it), lowering your fire rate considerably. In addition, all but one of those will actually home on ship.
* MostWonderfulSound - The extra life sound. The Neo variant even has a ringtone for it in Japan.
* SequelDisplacement - In fact the the first port was the MSX one.