Which *player* buffs stack. Like I know BladeDancer buffs will stack with say PP or SE buffs. But are those the only ones? Do any of the orc buffs stack?
No, all the "standard" buffs available through Shillien Elders, Elden Elders, Bishops, Prophets, Warcriers and Overlords, where they overlap, do not stack.
Summoner buffs stack with songs, dances and normal buffs.
Body of Avatar does not stack with BTB.
Heart of Paagrio does (AFAIK) not stack with Chant of Life.
Resistance and Surrender buffs from the classes listed above as well as sorcerers, spellsingers, and spellhowlers do not stack with each other.
Blazing skin does not stack with freezing skin does not stack with chant of vengance/revenge (not sure about the name, the warcrier buff in any case); all four do stack with song of revenge.
Elven self-buffs Spirit Barrier, Attack Aura, Defense Aura, and Sprint do not stack with respective prophet and orc buffs. I'm not sure about the tank MDef skill.
Majesty stacks with shield.
Orcish and human fighter self-buffs with the exception noted above stack.
The buffs a summoner applies to his or her servitor can be overwritten by a prophet (do not stack).
And while we're talking about stacking, I have heard that buffs that add holy properties dont stack. So that holy blade (Pally and SwS toggle), Holy Weapon, and Dance of Light dont actually stack, although they do all appear on your buff bar. Can anyone actually confirm that having more than one holy attack buff does or doesnt add more damage over just one of them? I'd be kinda interested to know.....