Clerics: there are no Clerics, per se; instead, every clerical character is a priest, and follows all of the rules in the PHB regarding priests except the following:
1. Priests are allowed to specialize in the chosen weapon of their deity. This normally only applies if the deities' weapon has a name, such as Mjolnir (Thor). It may apply, however, if a deity has a chosen weapon that figures into his symbolism, or is described as always wielding one specific weapon, such as spear (Zeus), which symbolizes his lightening bolts.
2. Demi Human Priests may multiclass, so long as the two classes don't conflict, i.e. a Priest of Athena may not multiclass with thief, although she could easily multiclass with fighter. Elven priests are all druids, and may multiclass with fighter or mage, but not thief or ranger. Note that alignment must also agree, i.e. a dwarven priest may multiclass with thief only if the priest is chaotic, and the deity is appropriate (Abbathor in Forgotten Realms for example).
Wizards: Wizards follow the standard PHB rules with the following exceptions:
1. There is no Read Magic spell; there is instead a language, called Majica in the common, which wizard and bard characters receive for free at 1st level. Any character adding the mage class at a later date will have to pay for the language with a proficiency slot. Priests of a deity of magic, such as Hecate, also receive the language for free at 1st level. Elves have their own version of Majica; speakers of the Common Majica cannot read Elven Majica unless they buy the language with non proficiency slots.
2. Additional Wizard Options: any school of philosophy, effect, or thaumaturgy from the Players Options books may be approved after consultation with the DM. Rules will follow those in the books.
Warriors: Paladins and Rangers are allowed to specialize in a melee or ranged weapon; Rangers are allowed to reach Expert level in either, but only single classed fighters may further their specialization beyond Expert.
Multi Classing:
the following classes may never be multiclassed unless specifically stated: Paladin, Bard, Specialist Wizard (except Gnome Illusionist), Monk.
Half Elves may multi class ranger with druid, but not priest.
Halflings may multi class fighter with priest.
Kits: Kits have the following new/adjusted rules: Kits may be acquired after 1st level. If a character without a kit encounters a NPC or group that is capable of teaching him that kit, he may acquire the kit after a certain amount of time is spent. For example a fighter who leaves home as a plain fighter travels to Waterdeep where he makes friends with some gladiators. The gladiators talk him into joining their team, and after a few months of training he gains the gladiator kit and all it's benefits. Campaign situations that change may also influence a kit change; consider a campaign where a despotic ruler is crushing the commoners beneath him; a party of Outlaw and Peasant Heros' and what not is drawn up to fight the evil ruler, and eventually they succeed. Once order has been restored and the people are freed, what does the group do? Their kits become useless, and they would either need to switch kits or drop the kit altogether and go kitless until other campaign situations call for a new one.
Kits may also stack; a fighter with the barbarian kit who journeys to Waterdeep and encounters the same gladiator team, or is captured and enslaved by a gladiator owner, can after a certain amount of time, gain the gladiator kit. At that point, any special benefits of the barbarian kit (bonus to reaction rolls) or special hindrances no longer apply, only the special benefits and hindrances of the new kit, in this case gladiator. You cannot lose proficiencies by changing kits, however you also may not receive free proficiencies of any kind from taking a second kit; you will have to pay for any required proficiencies out of new proficiency slots. 1st level characters can only begin with 1 kit; no character may ever have more kits than their additional languages number for INT, but regardless of that number are always entitled to 2 kits, given that the conditions in game make it possible and realistic.
Multi Class characters are allowed 1 kit, but it must be a kit that agrees with both classes, for example a fighter thief swashbuckler, or a fighter/priest barbarian (shaman).
Be aware that kits can and often do cross over class or even book divisions; for example, the equarry kit in the Paladin book would be equally acceptable for a fighter or a ranger.
Alterations to existing kits:
The following kits are not available and have been replaced or otherwise simply deleted:
Complete book of Elves: Spellfilcher
Complete book of Gnomes and Halflings: Buffoon
Complete book of Rangers: Greenwood Ranger: not barred, but see me first
Complete Priests' Handbook: Fighting-Monk
Complete Bards' Handbook: Jester, just because!
New Kits: I am always open to suggestions from players for making a new kit, if the idea is strong and the player is willing to put in the work on the kit. So feel free to shoot me an idea if you want.
Fighters:
The Martial Artist replaces the Fighting Monk from the Priests' handbook. This is a strictly combat oriented version of the Monk; for a true spiritual form of the Monk, such as the 1st edition version, this game will use the 1st edition version of the Monk. But a Martial Artist is a fighter who has specialized in unarmed combat as well as armed, in extreme physical conditioning, and feats of dexterity and strength that would boggle the ordinary humans mind. Official sponsorship of the Martial Artist is rare; they tend to be lone wolves, or part of a very limited sub culture in an urban area. Martial Artists rarely serve in military operations, as they have little value on a battlefield of tank warriors pelted with volleys of arrows. However in stealth missions, the Martial Artist can come in handy, and in these cases may find employment of at least the contractual sort.
Requirements: Str 12, Dex 12
Secondary Skills: Any
Weapon proficiencies: the Martial Artist receives 2 free slots at 1st level, which he must used to specialize in Martial Arts; all other proficiencies may be spent as desired, except to specialize in any weapon. Weapon specializations may come at later levels, but not first.
Non Weapon proficiencies: Bonus: tumbling, endurance.
special benefits: only the Martial Artist may continue specialization in Martial Arts as a fighter can with weapons. There is no limit to how far a Martial Artist can extend his mastery of martial arts. Further, though the Martial Artist is barred from wearing armor of any sort, he receives a special bonus to his AC equal to his level -1; in other words this benefit is not realized until 2nd level. This does not stack with the bonus for weapon mastery and above. Instead, when the Martial Artist achieves expert level in Martial Arts, he becomes able to strike foes that can only be struck by magical weapons. Finally, the Martial Artist learns the thieving skills Hide in Shadows, Move Silently, and Climb Walls as a thief of the same level.
special hindrances: the Martial Artist may not use armor or shields of any kind.
Race: only human