Call of Cthulhu d20 Remix

 Setting aside any particular feelings about the d20 system and license, I find the d20 variants of various games to bee a great gateway to other styles of play.

Similar to my discussion of Mutants & Masterminds and Star Wars, I decided to take the d20 Call of Cthulhu system I already owned and was familiar with and adapt it.  First, it almost goes without saying that CoC is essentially a one-shot game and not one for long term campaigns. Second, I wanted something that could be used as a general "horror" game, from Scooby Doo, to Slasher Films, to Zombie Survival.  With those ideas in mind I went about adapting the core rule book.

Power Level: Borrowing from Mutants & Masterminds, instead of character levels that one progresses through, I decide that the campaign or game has a Power Level that determines how accomplished/tough the characters will be.  These Power Levels (1-6) generally map to the character levels presented in the d20 CoC book.  I stop at PL 6 based on the ideas presented in D&D E6  where level 6 is the upper limit of "normal humans".

Class: I opted to smoosh the 2 classes presented in the rulebook into a single class.  Combined with the above Power Level, presents your characters with the following abilities.  Attacks, Saves, HP/AC, etc. are only adjusted by Ability Score Modifiers (which are generated normally) or Feat selection.

Power Level	Saves/Attack	Hit Dice	Skill Rank	Feats/Special
1	+0	1d8 (8hp)	4 / 2	1st, 2nd
2	+1	2d8	5 / 2
3	+1	3d8	6 / 3	3rd
4	+2	4d8	7 / 3	Ability Boost
5	+2	5d8	8 / 4
6	+3	6d8	9 / 4	4th

Skills:  I condensed the skills down to the standard dozen or so we see in modern d20 style games. Acrobatics, Athletics, Deception, Devices,  Expertise, Heal, Insight, Occult (Mythos), Perception, Sleight of Hand,  Stealth, Survival, Vehicles, and Wealth (see below).  Characters get the equivalent of 4 skill points per level (16 at 1st level).  I short hand this to pick 4 skills you are "Good" at for Max rank, or pick 8 skills you are "OK" at for half rank.

Wealth:  I generally like the idea of the wealth mechanic in games that feature "modern" notions of capital, banking, etc.  It speeds up character creation and play by allowing for a roll to determine if a character has or can acquire some random thing.  Also makes for quick "bribe" checks. So I do away with the actual dollar amounts, and treat Wealth as a skill.

Base starting wealth = 3 (+ Profession Modifier + Cha Modifier).  The Wealth Feat will also add +2 per use

Weapons: Characters all begin with "Simple" weapons, and can gain more based on their Occupation features or Feat selection.  Weapons are broken down into "Proficiency Groups", and I use the simplified firearm stats rather than track specific make and model.

• Simple Weapons: small blades, clubs, canes, improvised weapons/tools, fists (1d4-1), etc.
• Melee Weapons: swords, batons, bayonets, etc.
• Ranged Weapons: bows, crossbows, slings, thrown weapons
• Firearms: Handgun, Rifle, Shotgun, etc.
• Handgun: d10/x3 crit, 20' base range
• Rifle: 2d10/x3 crit, 200' base range
• Shotgun: 2d6, 25' base range
• SMG: 3d10, 25' base range

Sanity: I stick (mostly) with the sanity mechanic in the book (it is not my favorite since it tries to map too closely to real world mental illness) so that I can stick with using one book/resource while running the game.

• Starting Sanity: 10 +Con +Int +Wis +Cha - Occult Ranks
• Sanity Break: Loss of Sanity = to 1/2 Wisdom Score in 1 go, result in Temporary Insanity (per chart in book)
• Insane: loss of 20% (starting) Sanity in 1 hour of Sanity = 0.
• Unrecoverable: at -10 Sanity
• Recovery: Through long term care characters can regain d6 Sanity per month.

Characters: Putting it all together I create some basic stock characters (Detective, Psycho Analyst, Blue Collar Worker, etc.) then the player's pick one and customize it.

GM Notes: Finally I make myself a cheat sheet/GMs screen of the house rules, sanity/weird happenings tables, and spell effects. All told it is about 5 pages, with most of that being due to keeping all the table info cleanly formatted.