Crosses: Crosses are a mere annoyance than anything to elders, newer vampires would get burned /if/ it touched them. Elders would simply regenerate the damage and shrug it off.

Silver: Silver hurts, period. Newer vampires, again, are weaker. Elders, while still vulnerable, will heal it at a moderate pace, the flesh slowly forcing the silver out as it regrows.

Holy Water: New vampires worst enemy, especially vapor. Elders, In great amounts proves troublesome, small amounts you are basically poking them with a damned toothpick.

Running Water: Does jackshit to anything, ever.

Blessed Iron: Neh...Concept seems a bit...eh. Not sure how one would bless a chunk of metal..

Dead Man's Blood: Hinders healing powers, large doses can damage. Almost useless, but handy in a pinch.

Poison: Younger vampires could be susceptible, depending on age. Does nothing to elders, whatsoever.

Acid: What hurts flesh, hurts flesh. That simple.

Stakes: RIP

Sunlight: Possibly slightly annoying, does nothing other than that

Garlic: Could be used to deter younger vampires from you, elders simply find it appalling but not hindering.

Fire: Burny burny. Though, Elders might be able to regenerate it faster than it can harm them.

Decapitation: This is a bit iffy, as in one of the previous RP's Mithias regenerated from a pile of nothing. But, then again, he was in Stein's machine..So I'm gunna say it's a instakill, basically.

Old Magic: Not sure what you mean, this RP doesn't use magic o.O

Did I miss anything? :D