Overall the series is comprised of four games, which are however barely related to one another:
- Beast Busters (arcade, 1989)
- Beast Busters - Second Nightmare (Hyper Neo Geo 64, 1998)
- Dark Arms: Beast Buster 1999 (Neo Geo Pocket Color, 1999)
- Beast Busters Featuring KOF (Android and iOS, 2014)
A pachislot machine inspired by the latter game was also produced by SNK Playmore in 2015.
The franchise as a whole has examples of the following tropes:
- Oddball in the Series: Dark Arms is not a light gun/shooter game like the others, but an overhead action RPG. It's also a Castlevania-esque dark fantasy title rather than sci-fi horror like the others, and it was developed by Noise Factory rather than SNK.
Beast Busters contains examples of:
- Alien Invasion: The actual reason behind the zombie epidemic.
- Alliterative Name: The player characters are named Paul Patriot, Johnny Justice and Sammy Stately.
- Animorphism: Stage 1's boss is a leather-clad knife-wielding zombie punk that, after being shot enough times, turns into a yellow dog for some unexplained reason.
- Barbie Doll Anatomy: Stage 4 is set along a river and as such in its waters there are several naked male and female zombies, which lack attributes.
- Body Horror: One late-stage boss appears to be a sentient armed Jeep, but shooting off enough of the vehicle body reveals it to be a monstrous, fleshy thing of the same approximate shape, wearing a Jeep body as a carapace.
- Boss Rush: Stage 7 has the heroes confront clones of all the previously killed bosses and mid-bosses before the final enemy.
- Cute Monster Girl: Absolutely inverted regarding the female zombies. Most, if not all, of them are identical hags that are reminiscent of Iron Maiden's Eddie the Head.
- Destination Defenestration: Level 2 starts with two zombie gunmen ambushing you in a glass-panel elevator, both of which you dispatch by blasting them out through the glass.
- Dual Boss: A couple of muscular zombie twins wearing hockey masks (and not much else) at the end of stage 2. A trio of zombie bikers at the end of stage 3.
- Downer Ending: The final enemy has been defeated, but the alien invasion had just begun, since the heroes are horrified to see a gigantic spaceship hovering above the town. Also counts as Bolivian Army Ending.
- Giant Space Flea from Nowhere: Most bosses and mid-bosses are random monsters and things unrelated to the zombies. But they could be results of the aliens' experimentation.
- Incongruously-Dressed Zombie: A few of them are American football players, oddly enough always carried by zombie owls/eagles.
- Jump Scare: Some versions of the arcade have a zombie's head popping up from below and covering the whole screen during the attract mode, specifically during the explanation of the various weapons and bonus items.
- Ludicrous Gibs: If zombies don't explode in a myriad of pieces, it means they're not really dead.
- Mad Scientist: The final boss is one of these, sitting on some sort of cybernetic throne. Apparently he was the originator of the zombie plague. He's actually an one-eyed alien Brain Monster disguised as a human for some reason.
- Mr. Fanservice: For some reason several male zombies are shirtless or naked and have muscular bodies and chiseled features.
- No Celebrities Were Harmed: Sammy Stately resembles Chuck Norris.
- Our Zombies Are Different: Blue- or grey-skinned zombies that are able to drive vehicles and operate firearms. Somewhat justified in that aliens made them.
- People Jars: The cloned bosses during the Boss Rush stage are kept in stasis inside transparent jars, and bursts out to attack you on sight.
- Raising the Steaks: Zombie dogs, bats, owls and fish among the enemies.
- Rewarding Vandalism: Inverted. Shooting the buildings' and the subway's windows, as well as the glass capsules in level 5's corridor, will only make other enemies appear, and the stages are already overcrowded as they are...
- Sequential Boss: The final fight is one example. After the Mad Scientist gets defeated and exposed as an alien brain monster that phases in and out the walls while shooting missiles, beating him will have his remains crawl into a weird giant contraption that has to be destroyed piece by piece, after which the game finally ends. But the alien invasion just began...
- 20 Minutes into the Future: The game was made in 1989 and is set in 1999.
Second Nightmare contains examples of:
- Boom, Headshot!: This time you can defeat zombies immediately by blowing up their heads. It's also part of the scoring system: if you manage to blow off the zombies' arms and then their head you'll get many more points.
- Featureless Protagonist: The playable character are marine commandos, but other than that absolutely nothing is shown or said about them.
- Giant Space Flea from Nowhere: The final boss, some kind of weird floating giant eyeless monster that throws meteors.
- Kill Sat: The third and final tier of available bombs, it's much less effective than it appears.
- 20 Minutes into the Future: Again, the game is set about ten years after the year it was made.
