Short list of what different guilds gain from "Mark 2" aka "MK2" stats. Note that not all guilds have unlocked these yet.
(Thu Sep 18 16:37:50 2014) Belannaer <news>: Added 4 new equipment stats. Heroism/spellcraft (melee/caster) generally affects minimum effects of masteries and some specials. Ascendancy/dominion (melee/caster) generally allows you to push over the normal boundaries of masteries and some specials. For example in case of mage swarms spellcraft increases the minimum amount of projectiles casted and dominion increases the potential maximum amount of the projectiles. These new stats cap to 50 like old "new" stats (celerity/thaumaturgy etc.) do. Can be only found in new items.
NOTE: things may have had changes that may or may not be included here, because sometimes when a news-post is made, it does not include the skill/spell/thingy name and it is only referred to (like "previoust post" etc), or sometimes people may miss a News announcement, or search for them with wrong keywords, so some stuff might be missing, if so, let me know (Ezenya ingame, send mudmail preferably, or try to get a hold of some moderator for this site ingame).
Army of Vaerlon:
Heroism lowers ep cost of maneuvers including those procced by devising combat maneuvers. It also increases the chance of two-handed strength and scything strikes. Ascendancy increases damage of army maneuvers and gives small chance to perform melee brutalities when wielding weapons two-handed.
Conclave of Sorcerers:
Heroism lowers the cooldown on martyrdom heal and increases fury gain for firepriests.
Ascendancy can give additional juxtapose copies when throwing for fire priests.
Ascendancy now also makes passionate preaching easier.
Mages of Valkor:
Intelligence and spellcraft now has an effect on reducing sp costs of spells for Mages.
Scions of cursed blood:
Ascendancy stat now boosts the current soul collections of dhamphirs. Brelasean branch benefits from both dominion and ascendancy, but so far only in a passive way in some effectivity calculations.
Dominion stat now increases blood max for Water priests, increases special effects of spellbinding spells, increases base damage of spellbinding spells and makes auras more powerful. Karmic justice normally scales with the amount of blood you have. Dominion stat now increases the base amount to be at certain level even if you don't actually have that much blood at the moment.
Spellcraft now increases the amount of spellbinding points you get per each tick from your casting points. It also increases the chance of channeling (not spellbinding) spell specials. And it adds a chance to mana burn your target (if not player) per each tick as an additional effect and chance to mana burn your target when a spellbinding spell finishes (uses the same auto-targetting on opponents as spellbindings if you are for example funneling party member). Chance to gain mana drain from mana burn is also increased by it.