* AnticlimaxBoss: The true final battle of ''Infinity Gene''. [[spoiler: And then the solitary final invader, which is arguably harder than ''even the boss before it''.]]
* DisappointingLastLevel: Taito was either short on budget or time when coming up with ideas for ''Space Invaders Extreme 2''[='=]s final stages, because two of those four final stages' tracks are "invAde yOu aGain" and "Outbreak→Pandemic", which are just slightly rearranged versions of the Stage 1 and 2 tracks from ''Extreme''.
* FirstInstallmentWins: Games after the original tend to not be remembered very well.
* GameBreaker: Several in ''Infinity Gene'':
** The Field ship. It slams anything within the targeting circle for extensive damage, and at max power, the circle is wide enough to cover the entire vertical height of the screen. It makes swarms of enemies practically trivial; any enemy that's a OneHitPointWonder and is unfortunate to spawn within the circle won't even have a chance to appear on the screen!
** Variable isn't quite as "kill everything around you" as Field, but any enemies caught in the laser swords is in for a world of pain. Even better if you get all four swords on a single target.
** Classic, which kills anything in a single hit. ''Even bosses.''
* GeniusBonus: The names for some of the stages in ''Infinity Gene''.
** The very first stage, "Common Descent" is like that of an old-school arcade space invaders game. These invaders are the common ancestor of the other enemies you will soon face, hence the other enemies share a common descent.
** The final stage (after the FinalBoss), "Back Mutation" has you fight a single lone invader in an old-school arcade format. A back mutation is a mutation that reverts a gene back to its original self.
** "Struggle for Existence" has a BossRush of 8 or so minibosses before encountering the real boss itself.
* GoodBadBugs: The point value of the flying saucer in the original version appeared random, but was actually a function of how many times the player had fired. A savvy player could count his shots, wait until his shot count got up to 14, and ''then'' shoot the saucer, guaranteeing himself a whopping 300 points.
** In the original game, when the Invaders are at the bottom row, their bullets generate under the player's turret, rendering him immune to that row's attacks. This technique is called ''Nagoya Shot'', so named for allegedly being discovered in Nagoya. ''Space Invaders Extreme'' references this with the "Nagoya Attack" bonus for Invaders that move in the traditional side-by-side pattern; Invaders destroyed on the bottom row yield a 20x score multiplier. Also referenced in ''Space Invaders Infinity Gene'', where there's a point reward for exploiting a similar (deliberate) feature where enemy shots don't hurt you for the first second they're on the screen, once you unlock it.
* PolishedPort: The iconic Atari2600 port of the game. While the graphics are a step down from the already primitive arcade game, the gameplay is uniformly considered just as good, if not superior to the arcade game, owing in part the staggering variety of gameplay options available on the cartridge.
* ThatOneBoss: The final boss of ''Extreme 2'' at at least 5-D is the closest Space Invaders can come to BulletHell. It can use a ton of different shots and has three seperate targets, each with its own massive amount of health. Extreme 5-C is considered to be one of the, if not the, hardest bosses in the franchise, and non-Bullet Hell shooters as a whole.