Resident Evil: Revelations marks a return to the survival horror roots of the franchise from the action-centric gameplay of the previous title, Resident Evil 5 .
The game takes place before part five in 2005, and after the total destruction of the ultra-modern sea-based city of Terragrigia by terrorists using old Umbrella-style B.O.W.s, or Bio-Organic Weapons. The primary focus of the story is on Jill Valentine and Chris Redfield as they hunt for answers on a mysterious luxury cruise ship known as the Queen Zenobia. The story is broken into chapters fitting for a portable title; story-wise, chapters alternate timelines. Jill Valentine works with her new partner Parker Luciani for the BSAA (Bioterrorism Security Assessment Alliance). Alternate story segments may focus on Chris Redfield and his new partner Jessica Sherawat, or new BSAA members Keith and Quint. Each chapter is intended to gradually wrap together the full narrative.
Exploration in the game is done in third-person 3D, but with a more traditional survival horror gameplay style, similar to Resident Evil and Resident Evil 4 . Players are once again exploring an ornate and luxurious environment carefully monitoring ammunition, approaching puzzles, and choosing when to fight and when to flee from an attack. The new mutations also appear in smaller numbers, and in claustrophobic areas.
While exploration of the Queen Zenobia is deeply rooted in the survival horror style, many alternating chapters are much more action-oriented and resemble the "shooting gallery" segments of Resident Evil 5 . These segments may also include classic B.O.W. monsters, such as the infamous Hunters and variations of zombie dogs. Ammunition is plentiful, and exploration is downplayed.
New to the series is the Genesis device which allows players to scan their environments for hidden items, such as ammunition or hand-prints, or to scan enemies for "data." Each enemy scanned increases a few percentage points, and scanning to 100% grants the player a new herb. The inventory slot system is largely removed, and players are given general limitations instead--up to three weapons and five herbs may be carried at once, and weapon upgrades can be applied to any weapon.
A special Mission mode exists that operates like an Achievement system in an Xbox 360 game. Completing the various missions unlocks the multi-player Raid mode and special items and circumstances for Raid mode. The Missions also utilize the Nintendo 3DS's Street Pass functionality, which may unlock other missions should the player's 3DS encounter another with different active Missions.
The game is primarily played on the 3D screen of the Nintendo 3DS, and even includes an option to effectively double the depth of the 3D on the system. The touch-screen is used for inventory, item details, and the game's map. Primary and secondary weapons may be selected on the touch-screen, as well as the Genesis device.