ToME: the Tales of Maj'Eyal

Does it use the same damage calculations as described on the wiki here: http://te4.org/wiki/Combat_Damage

E.g., stone warden has Eldritch Slam: Slam your shield on the ground creating a shockwave. You perform a melee attack for X% Arcane damage against everyone within radius Y.

Lets say it was 200% arcane damage.

Does this mean my strength, phys power, stoneshield talent modifier, etc all are applied? Same as a bump attack, just without any added +dmg (melee)?

I assume it is calculated just off the mainhand shield?

What about Eldritch Fury instead?
"Channel eldritch forces into a ferocious melee attack, hitting the target three times with your shield doing X% Nature damage. If any of the attacks hit, the target will be dazed for Y turns. The chance for the attack to daze increases with your physical power, but it is considered a magical attack and thus is resisted with spell save, rather than physical save."

Same thing, but 3 attacks all using my str, phys power, etc, AND presumably getting the +dmg(melee) bonuses I have from equipment and any sustains/passives?

Would the 3 attacks use both mainhand & offhand (so 6 attacks)? Or just main hand?

X% weapon damage means exactly that: weapon damage (perusing damage mods, physical power and weapon power and range) is calculated, then multiplied by X%. On-hit effects are generally triggered with unmodified damage. (Yes, they're generally triggered -- the ones on the weapon itself, at least. It depends on the skill.)