Sohei Spell List Change: Add Read Magic as a 1st level spell.
Shugenja Spell List Change: Add Fly as a 3rd level Air spell.
Heighten Spell Elimination and Slot-based DCs: The Heighten Spell feat no longer exists. For ANY spell cast using a higher slot than its normal level, whether prepared/cast with metamagic or not, the DC will be determined based on the level of the spell slot used, not the level of the original spell.
Spontaneous Casters and Metamagic: When a spontaneous spellcaster (i.e. sorcerer or shugenja) uses metamagic to enhance a spell which normally is cast as a standard action, the spell is cast as a full-round action -- but it does NOT become a 'full round spelll' with respect to casting time. Essentially, the act of preparing a spell with metamagic is a move-equivalent action which can provoke an attack of opportunity and which occurs immediately prior to casting the spell. Thus a spontaneous caster can take a 5' step and cast a metamagic-enhanced spell as a full round action, with the spell taking effect at the end of his turn -- NOT immediately prior to his next turn, as a spell with a full round casting time would.
Haste Spell Change: This spell is as per the PHB (3.0) description, except that the partial action granted may only be used as a move, move-equivalent, or attack action. The recipient must still use the extra partial action either before or after his regular action, still gains a +4 haste bonus to AC.
Summoned Monsters: In Drakara, a combination of elite individual monsters and random average monsters may be summoned, as follows:
When a spellcaster summons a specific type of monster, the first 'N' monsters summoned are all specific elite individual monsters, where 'N' is the maximum number of monsters of that type the spellcaster can summon with a single spell. For example, a spellcaster with Summon Monster III can summon 1 celestial bear (from the SM III list) or d3 formian workers (from the SM II list) or d4+1 fiendish dire rats (from the SM I list) -- so the first celestial bear, the first 3 formian workers, and the first 5 fiendish dire rats that spellcaster can summon are elite individual monsters. If the spellcaster cast Summon Monster III twice in a row and ended up with a total of 4 summoned formian workers, the first 3 would be elite individuals, the fourth would be a random average formian worker.
For each type of creature the spellcaster can (and chooses to) summon, the spellcaster defines an 'elite template' which determines the characteristics of the elite individuals which answer his summoning spells. The template determines the ability scores of the elite individuals as follows -- the spellcaster takes the average ability scores for the monster from the MM and applies elite modifiers to them, assigning +4, +4, +2, +2, +0, and -2 to the six ability scores in whatever order he wishes. The spellcaster then adjusts the monster's skills to reflect any change in the appropriate ability score for each skill. (Number and allocation of effective skill points the monster has is not changed even if INT is modified.) The spellcaster also adjusts the monster's saves to reflect new ability scores. Each elite individual the spellcaster summons uses this one elite template.
For each elite individual, the spellcaster records the monster's name and hit points -- hit points are rolled normally, based on the monster's hit dice plus current CON modifier, however if hit points are less than the average hit points for an average monster of that type, as given in () in the MM, the monster has the average hit points instead of the rolled hit points. (This is regardless of the elite individual's CON, although of course an elite individual with an improved CON is less likely to need to use the average hit points, while a an elite individual with a reduced CON is more likely to use them.) Also, if the monster has any skills for which a choice must be made (such as a formian worker's Craft(any) choice), each elite individual may be given its own choice of skill. (For average monsters beyond the spellcaster's number of elite individuals, the GM determines such choices.)
Additional rules may be found in the DMG, on page 96, regarding special considerations regarding summoning individual monsters -- these apply except where they conflict with the above changes.
Note that because of the combination of elite and average monsters, a spellcaster summoning multiple monsters in a row for combat purposes may well summon a variety of different types of monsters -- because although for instance an elite fiendish gorilla may be tougher than an elite celestial black bear, and an average fiendish gorilla may be tougher than an average celestial black bear, an elite celestial black bear is better than an average fiendish gorilla! This is a feature I wanted to encourage, hence the combination rule...