Mechanics:
This is intended to be a sort of adventure quest, and will thus revolve mainly around the MC - business empires and such can be built but will take almost obscene effort due to the resistance of vested interests. The stats are Strength, Reflex, Constitution, Intellect, Willpower and Charisma. Strength adds directly to your melee rolls, reflex to shooting, intellect to spells, willpower to SAN checks and suchlike, Charisma to social. Weapons and traits may allow other attributes to be added as well.
Skills are numerous, and I have allowed certain skills to begin unlocked. These are Infiltration, Firearms, Hand-to-Hand, Lore:India, and CQC. They in turn have subskills which confer further bonuses and are easier to level.
Levels are E-(0/100) -> E(0/200) -> D-(0/400) -> D(0/600) -> C-(0/800) -> C(0/1200) -> B-(0/1400) -> B(0/1800) -> A-(0/2000) -> A(0/2400) -> S
Each level below C subtracts 5 from related rolls, and not having the skill at all subtracts a further 5. Thus if one cannot shoot at all, any roll will have -30. Each level above C confers +5, and ranks of B, A, and S will allow trait selection for that skill - you personal twist, as it were.
Subskills are things like CQC:Spear, which gives bonuses to rolls with spear combat, and perks to spear combat. If you choose a weapon in character creation, you will unlock its skill and subskill at C.
Natural crits (rolls of 95+) will be cascaded, and crit-fails will have a mitigation roll on a d100 to gauge how well you can adapt to the reversal. Fail that (Roll less than the opponent, or less than the DC), and it's a full-blown failure.
Combat:
You will face foes who have a health amount and weapons and damage of their own. It's loosely based on DnD, so weapons will increase damage and so on. Roll for damage based on weapon, with Hand-to-Hand dealing damage based on a d4. Thus if I roll 6 and have 3 Reflex using a rifle, I'll deal 9 damage to my enemy, which will be mitigated by armor if he's wearing any. Armor acts as a damage sink with health of its own and resistance to certain types of damage, and entities can have resistance as well - Agni's fire will not burn a deva as much as a rakshasa.
Who strikes first will be determined by initiative on a d100, and it proceeds after that. Rolls to hit, to crit and suchlike are on a d100 and affected by your skills -> Damage is rolled only after score a hit. Thus is you cannot shoot, your roll is 1d100-30(no skill)+reflex, and damage rolled if the enemy cannot dodge and you hit them.
Magic:
There are more than one type of magic and magecraft. Three broad ones I'll introduce now are magecraft (like Dresden's), karmic abilities (Think of what brahmins and kshatriyas do in the Mahabharata - blessed arrows, armor of flame, increased luck, and so on.), and faith-based stuff from the Church (divine aid in searches, social, better luck, anathema to evil etc). The systems are described below:
Magecraft:
You have a mana pool that regenerates each turn, fuelling spells that you know. Your spells are roughly grouped into Evocation (Boom), Ritualcraft (wards, rituals, summons), Alchemy (think potions and so on), Divination (Little Chicago, blood-searches, warding against searches and so on). Further to be added as necessary, please let me know. They will follow the skill system above, and should you choose magic as a character perk, I will allow you to choose a focus area to get to D-Rank.
Spells are learned under each are, and have a cast DC (usually low->20 or so). They deal magic or elemental damage on a dice depending on the spell, and cost mana to use. Mana does not regenerate in combat, so be wary. When your mana reaches zero, you will have the Casting Fatigue malus: -2 to all physical damage dealt.
Spells and so on move from Apprentice(0/100)->Journeyman(0/400)->Master, and reduce mana required and increase effects per rank.
Potions will cost money to make and require a workshop of some kind. If you pick the Alchemy specialization on start, you'll have two potions of each type, and some items - namely a silver wire and stakes to set up a circle, and a recipe book. New recipes can be researched as projects that I'll allow die investment into, and you may also work in imbuing weapons and on transformation of material(enhancing steel and so on) at higher levels. Workshops are basically places where you can borrow a cauldron or container, set up a circle and make your potion in peace - as such places out of the fighting.
Potions may be sold to magical entities but cannot be used in public or sold or given to mortals for fear of breaking the masquerade. You can still do so, but the Wardens will hunt you down for it.
Karmic Abilities:
These are blessings and abilities granted by the old gods of India, who are slowly becoming active (or at least less sleepy) once more. You will have a resource called Karma that increases both per turn and depending on actions. Karma may be spent to buy increased damage during a combat miniturn, convert a fail to a success, and buy abilities. Abilities last for a specified number of turns or uses and are rather powerful to balance it out.
One example are arrows blessed by Agni. They'll be unnaturally accurate and burn everything around the hit area as well, dealing holy and fire damage on a d6+5. The downside is a karma cost of 2 per arrow, so spend them wisely.
Karma can also be reduced by going against a god, meddling in things they don't want you to and suchlike. There are many, many gods, so don't fear loss of your karmic abilities, but at the same time don't excessively piss off a god.
You may buy abilities at temples or through meditation and penance, to reach the deva you are appealing to. Cost may be reduced by bargaining or favors to the deva in question, although there are hazards there as well.
Faith-based abilities:
Similar to Michael Carpenter's insane luck, you have a resource called Faith that increases each turn and depending on your actions. Faith can also be decreased by actions contrary to the tenets of the faith (heh) and if you turn Denarian is replaced by a resource called Desecration with similar mechanics.
Faith can buy success in combat DCs, can save a crit-fail and can grant abilities/appeals. You may appeal for success in a search (see Charity Carpenter), you may ask for aid against the darkness (bonus holy damage), high Faith can see much-increased relations with the Church, and so on.
Faith is through prayer and appeals to God, and as such will always be a choice in an action. I will write in faith-based options in actions, and your character sheet will show appeals that have succeeded before and their faith cost.
You will also be able to consecrate weapons and temporarily consecrate areas by spending Faith, which will then do damage to demons and so on that are affected.