so to 1 shot boses at Silver spire Aspect of terror and Assasin of andriel/duriel/beleth you need.
build wich includes calatrops with 45% weapon damge and traps with 375% weapon damage. and AoE Mark of death.
also you need crsbow with 700+dps and socket with crit.
pasive skills: curse of weak/stedy aim/and one wich give +3% crit every second.
so you place all traps behind npc with you need to talk than boss spawn spam your Elemntal arow .
the glich on build is all traps will crit than boss spawn and prity much 1 shot it.