On DN ty/de is not that good in catacombs because of phsical resistance of mobs. ty/de as damage dealer + spoiler + pp/bp + bd/se + sws will rape in varka silenos. All you gotta do is set your healer to heal him only under 55% hp,even 30% hp if you have weapon with +25 health. Also give him 1 vampiric buff.
If you want catacombs I used this party
necro/sorc - gloom/debuffs - first hit
sps/es - debuff for aqua and hit with aqua after - follow the necro (use the seraphim buff for reuse time)
bd/se - mage buffs
pp - mage buffs
sws/ee (or only ee) for prophecy
Happy boting guys.