Beast Busters may not be as well-known as some of SNK's other franchises (i.e. The King of Fighters and Metal Slug), but it's older than both. The series first appeared in 1989, and it has since been eclipsed by other entrants in the light gun shooter genre. Watching the trailer for Beast Busters featuring KOF Deluxe will probably have you thinking of The House of the Dead.
Beast Busters featuring KOF came to Android at the end of 2014 as a free-to-play title bogged down by an energy system and in-app purchases. What makes the new version deluxe? It costs $2.99 and, according to SNK, no longer requires any additional payments to complete. That's not to say that the game is free of IAPs—they're just less intrusive. The energy system has also apparently gone away. In short, making the game deluxe means taking the original version and making it playable.
This mash-up title surfaced in celebration of the 25th and 20th anniversaries of Beast Busters and the King of Fighters, and it lets players gun down monsters as one of the brawlers from SNK's 2D fighter. It's a weird concept, but hey, at least now you can actually enjoy the game.
Alternate title: SNK Releases 'Beast Busters Featuring KOF' As It Should Have Been In The First Place (Thanks, someone755)