So con arura gives damage to hammers. How much damage does a level 20 con give to a magic abyss/chanins lock. I assume some one has tested this. Is it worth the price of pride for merc?

Conc aura gives exactly 0 damage to magic warlocks. It working on the magic damage Blessed Hammer is an exception, not the rule.

iirc conc giving damage to blessed hammer was originally a bug and people enjoyed it so much that they decided to keep it in the game.

conc doesn't do anything for other magic spells.