Inti Creates have nearly cornered the market on contemporary titles that feel like retro games. From their Blaster Master Zero series to the various Gunvolt entries, they are adept at making fun, brisk experiences that offer replayability and familiarity. Grim Guardians: Demon Purge is no exception to their signature brand of action; its level-based Castlevania trappings see the two heroines, Shinobu and Maya, make their way from floor to floor as they climb a demonic castle. Its signature gimmick of being able to swap between the sisters on the fly (or play co-op) makes its five to seven hours fairly enjoyable, but some of the gameplay tricks do wear a bit thin by the end.

When dimensions collide and the girls' school is amalgamated with the demon realm, Shinobu and Maya charge headlong into the dark, towering castle that stands in its place. Along the way, they'll rescue students trapped in its halls or taken prisoner by the creatures within. The girls also focus on searching for a man who may or may not be Shinobu's boyfriend/crush. At the top of the castle awaits the culprit behind the whole mess, who has a specific affinity for adding "HELL" to every statement she makes.

The gameplay is tight and fluid, with each sister possessing a different weapon and set of ever expanding sub weapons. Shinobu has a machine gun that allows her to attack from range, but it lacks the power of Maya's slashing weapons. Every time a boss is defeated you earn a new sub weapon, and many of these allow for greater exploration of the castle, whether it's blowing up cracked floors with Shinobu's timed mine or forming platforms with Maya's paper crane. Jumping, shooting, and slashing feel great, and there's almost nothing to fault about the action here, other than Shinobu's lack of mobility when opening fire or the need to regularly reload her gun.

Playing solo, when one of the sisters' health runs out, the other will respawn a slight distance away and be able to revive their downed sibling. Sometimes these checkpoints are further away, which can make the rescue mission a perilous one. If both sisters die, you'll lose a life, but this didn't happen to me too often, partly due to the revive mechanic and partly because the game’s normal difficulty isn't massively challenging. Fortunately, completing the game does open up a third, harder setting, and there's an easy mode for those who want a breezier playthrough. Finishing the game also unlocks a boss rush mode, and a couple dozen in-game achievements encourage return trips to the demon realm.

In the same way that Ghosts N' Goblins originally required players to return through it's stages to unlock the ending, Grim Guardians does something similar. After defeating what initially seems to be the final boss, an adult version of the boss appears and essentially forces you to backtrack through the castle to obtain five special items before you can reach the game's actual final level. It's a bit of a tired way of adding length, but some new abilities coupled with new paths to explore and more challenging boss patterns in their re-fights add variety to the backtracking.

All in all, Grim Guardians: Demon Purge is another satisfying 2D action title from Inti Creates, further cementing their status as makers of genuinely solid retro throwbacks. Some of the enemy designs are clever callbacks to Mega Man and Castlevania, but ultimately the title manages to stand on its own merits. Even though they never seem to stop dictating all the action happening on screen, Shinobu and Maya are delightful to play as and make enough banter and jokes between them to keep the narrative light. If you'd rather purge something new than the dozens of games in your backlog, Grim Guardians provides a devilishly fun ride.