How about Blood 3 only make it more of a sandbox FPS(with third person mode) or something like Crack Down where you have ?regions? to conquer, these regions can be different time lines or worlds (like medieval time, 1900s, future world, demon world, Heaven(a very warp version thereof), circus world, ect ). Each region would have a main hub and branch from there (and offer fast travel via the map) to unlock a new region you have to find it or be taken there via story. There should be some upgradable equipment that slightly alters how you play the game and 7-10 different weapon/spells per region.
Weapon/spells should be upgradable with merchants in all main hubs. Weapon/spells can be selected in your load out order and or taken between regions once unlocked(unlocking is a bit more complicated than just acquiring the weapon) . Pace out what can be carried to a max of 10 weapons and 10 spells. Basic stats like speed, jump height, defense, melee attack, range attack power, accuracy, reload time, health points, magic effect/attack power and magic points should be upgradable. Also there should be a few vehicle handling stats to enhance vehicle performance and handling. Gameplay would be similar to Bioshock but you get 4 quick attack buttons you can slot a grenade, weapon or spell to, change to grenade does not take much time but from weapon to spell there is some lag.
Or just combine Fallout 3 with Crackdown that would work too?.. LOL
Weapon/spells should be upgradable with merchants in all main hubs. Weapon/spells can be selected in your load out order and or taken between regions once unlocked(unlocking is a bit more complicated than just acquiring the weapon) . Pace out what can be carried to a max of 10 weapons and 10 spells. Basic stats like speed, jump height, defense, melee attack, range attack power, accuracy, reload time, health points, magic effect/attack power and magic points should be upgradable. Also there should be a few vehicle handling stats to enhance vehicle performance and handling. Gameplay would be similar to Bioshock but you get 4 quick attack buttons you can slot a grenade, weapon or spell to, change to grenade does not take much time but from weapon to spell there is some lag.
Or just combine Fallout 3 with Crackdown that would work too?.. LOL