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I took a lock to 80 with a demon spec all the way. It was really fun and easy and so were group quests. But I kept reading about how affliction was so good so I have just started a new lock and plan to go affliction all the way. I know that you can level in any tree, but wanted to see for myself what the difference was (if any). Since the felguard can hold agro better and hits harder than old blue I don't yet understand what the affliction tree has that will make up for this. Will I have to kite a lot because I now catch more agro?

I would really like to hear from anyone who has done both trees to help me understand the essential differences.

Thanks

I leveled my lock entirely as Affliction. At low levels, I tried the Drain Hunting strategy (use Void to hold aggro while you kill stuff). But by level 20 or so, I switched entirely to Drain Tanking (use SL portion of Corruption to heal you and Drain Life to keep yourself topped off) with the Imp as dps help.

This was back when Siphon Life was a separate DoT, but the concept still applies. Use Corr and CoA and Drain Life. Life Tap (or Dark Pact) to get mana back, get health from the mobs you kill...

I put my Imp on passive and just dot everything, use Haunt, drain life, dark pact when necessary.

Affliction doesn't utilize pets as much in soloing. Imp is there for the HP-free dark pact