My usual ruleset is ACKS so these are written with that in mind.
Classes: The following classes are always appropriate for any campaign I run: Fighter, Mage, Cleric, Thief, Assassin, Bard, Explorer, Dwarven Vaultguard, Dwarven Craftpriest, Elven Spellsword, Elven Nightblade, Anti-Paladin, Barbarian, Dwarven Delver, Dwarven Fury, Elven Courtier, Elven Enchanter, Elven Ranger, Mystic, Paladin, Shaman, Warlock, Witch. The remaining classes sort of depend on the campaign-- ask me if you're not sure.
Cleric Weapons: Clerics can choose to use either their usual weapon selection or that of shamans (Club, dagger, hand-axe, short sword, staff, spear). Other narrow weapon selections, within reason, are also okay.
Turn Undead: A cleric can turn any evil creature as if it were an undead of comparable hit dice. For purposes of this spell, evil creatures include inherently evil creatures such as undead and summoned creatures of Chaotic alignment.
Cleric Spell List: Clerics make the following changes to their spell list:
- 3rd level: Feign Death no longer exists, Prayer takes its place.
- 4th level: Sticks to Snakes is not on the Cleric list, Death Ward takes its place. (My grievances with this spell are well-known. I don't mind Shamans having it, but I don't have a ready explanation for why.)
Additional Spells: If a character can cast spells and has a prime requisite of at least 13, they gain the ability to cast an extra first-level spell per day at the time of character creation. If a character can cast spells and has a prime requisite of at least 16, they gain they gain the ability to cast an extra second-level spell per day as soon as they gain the ability to cast second-level spells. If a character can cast spells and has a prime requisite of 18, they gain they gain the ability to cast an extra third-level spell per day as soon as they gain the ability to cast second-level spells.
Unusual Equipment: If you want to buy something out of the ordinary (ie not elsewhere listed in the rulebook or by me), Zak's Penny, Nickel, Dime, Quarter, Dollar rule is in effect.
Dullness/Fastness: Sharpness and Slipperiness are both reversible spells. The effects of Dullness should be obvious (-1 to attacks with the weapon, but it still becomes magical). The effects of Fastness are thus:
When cast on a character, the recipient cannot be restrained or grabbed,wrapped in the grip of constrictor snakes, or otherwise be subject to any other grasping attacks, including binding ropes, chains, or cuffs, magical or otherwise. Simply put, nothing can get a grip on a character affected by slipperiness. The spell can also be cast on objects. A single casting is sufficient to affect 20 arrows, 2 one-handed weapons, 1 two-handed weapon, or one 10' x 10' patch of floor. Any object subject to the spell is virtually impossible to grasp, and characters must make an attack throw versus Armor Class 10 each round to let go of or throw such objects. The object can instead be used to bind two objects together. A proficiency throw of 20+ is necessary to pull them apart. Any individual moving or even standing on an affected area of floor must make a proficiency throw of 20+ each round or remain rooted to the spot.
Climbing Huge Opponents: If a combatant is significantly smaller than her opponent it may be possible for her to climb onto her opponent to find a better point to attack from. To climb an opponent, a combatant must succeed on a melee attack throw with a -4 penalty. The opponent must then make a saving throw versus Paralysis. If the opponent succeeds on his saving throw, he has shrugged off the combatant. If he fails, the combatant has climbed on. A combatant who is climbing an opponent may perform a brawl or regular attack at a +2 bonus so long as she stays on. The climbed-upon opponent may make another saving throw versus Paralysis each round to attempt to shake off the opponent, or may attempt to wrestle it. A combatant capable of backstabbing may backstab a creature she has climbed. A combatant capable of climbing walls may make a proficiency throw to hang on or avoid a wrestling attempt from a opponent she has climbed. Any bonus that affects attempts to wrestle also affects attempts to climb an opponent.
Shields Shall Be Splintered: A shield can be sacrificed to nullify all damage from a single attack, however if the attack does at least 6 damage in a single attack, the defender takes 1 point of damage reflecting the smash being hard enough to hurt their arm. Magical shields can absorb one additional blow per day per point of additional protection. Magical shields can also deflect spells of a level no higher than their enchantment bonus that specifically target their wielder once per day in place of an attack, or any spell a single time, but so doing breaks the enchantment on them and instantly destroys them. (Yes this makes magical shields really awesome-- that's sort of the idea)
The Life-Drinkers: Creatures that drain levels... don't. I've never liked this mechanic, even in old school games where it's that much less involved. Instead I've
Energy Drain: An attack that would ordinarily drain a character's level instead deals 1d6 damage and imposes a cumulative -1 penalty on all attack, saving, and proficiency/ability throws. If the penalty exceeds the character's level, she dies. 1 point of energy drained is recovered every L days where L is equal to the hit dice of the monster that drained the energy level.
Vampiric Bite: If a vampire Charms a living creature, the creature is willing, or the vampire successfully grapples the creature, it may bite. The bite deals 1d3 damage and drains 1d3 points of Constitution per round much as a Shadow does strength (for creatures without constitution scores treat its HD as equivalent to its constitution score). The vampire heals 1d6 damage for each round it drinks of the blood, but while it is so occupied all attacks against it are made as if the vampire were surprised.
Spectres: Paralyzing Strike: a spectre's touch paralyzes as a ghoul's. Terrible Aura: The palpable aura of fear freezes all those who see a spectre. Save versus paralysis when first encountering the undead or be paralyzed for 1d6+1 rounds. Possess: a spectre can possess any corpse. While so doing, the spectre cannot be harmed until the corpse is destroyed. It fights as a zombified version of whatever it was in life. Vampires: Vampiric Bite: If a vampire Charms a living creature, the creature is willing, or the vampire successfully grapples the creature, it may bite. The bite deals 1d3 damage and drains 1d3 points of Constitution per round much as a Shadow does strength (for creatures without constitution scores treat its HD as equivalent to its constitution score). The vampire heals 1d6 damage for each round it drinks of the blood, but while it is so occupied all attacks against it are made as if the vampire were surprised. Wight: Putrefying Aura: The wight is a creature of decay and death. In its presence milk curdles, bread moulders, meat rots, water turns brackish and swampy, and wine sours to vinegar. Any food or drink that comes within 20 feet of a wight spoils immediately and must be treated with Purify Food and Drink before it can be safely consumed. Withering Touch: The claws of a wight spread its decay. Any normal plantlife touched or trod on by a wight dies. Magical plants and living creatures take 2d4 damage and seem unnaturally aged until they heal. Wraith: Cursed Wound: The blows of a wight inflict a terrible pestilence. They do not heal for a year and a day unless Remove Curse is cast upon the victim. Even then the scars will always ache on the anniversary of the day they were inflicted. Creature of Darkness: Wraiths can cast Darkness at will. Soulbound: Wraiths are born when a mortal succumbs to the corrupting influence of an evil magic item-- most often a cursed weapon, suit of armor, or ring-- which will always be present among their treasure in addition to whatever else of value they have. Whatever the item, it is sentient in the manner of certain magic weapons, is chaotic in alignment, and can only be disposed of via a Remove Curse spell. If the item's new owner dies while under the influence of the item, he rises as a wraith in 24 hours.
The Petrifiers: Petrification, except via the Flesh to Stone spell, is not an instantaneous process. When you fail your save, roll 1d6 for the number of rounds you have left to fight, strike a cool pose, or whatever. You are slowed during that time, and during the final round you are outright paralyzed. Any creature naturally capable of turning a creature to stone also knows how to turn a petrified creature back with a touch. Medusae cure petrification with their hands, basilisks with a slap of their tail, and cockatrices with a bite. A creature that has been restored from petrification is paralyzed until such time as healing magic is used to cure its paralysis. Normally they use this ability in order to restore their prey to an edible state, however intelligent ones such as medusae can sometimes be bribed or persuaded into doing it in exchange for mercy if subdued or in exchange for favors (usually involving undertaking a quest).
Golem Spell Immunity: Golems aren't completely immune to magic, however they are highly resistant to it. Unless a spell is specifically or implicitly named in their description, if it has a save they automatically succeed at that save. If it doesn't normally have a save, it does when used against a golem. (I don't think the golems in ACKS core actually have spell immunity, but I use the standard AD&D ones and that's the rule I use for them too)
Wraith Hoards: Wraiths are born when a mortal succumbs to the corrupting influence of an evil magic item-- most often a cursed weapon, suit of armor, or ring-- which will always be present among their treasure in addition to whatever else of value they have. Whatever the item, it is sentient in the manner of certain magic weapons, it is chaotic in alignment, and it can only be disposed of via a Remove Curse spell. If the item's new owner dies while under the influence of the item, he rises as a wraith in 24 hours.