He said THIRD level. Necros are only on the 2nd >,>
Basically : if you can't handle the Zombie Slaughters and Ragged ones, and you're not decent with gears, go to the third level, just banshees and flame skulls. Just carry some flywings incase you run into beelz.
1st lvl : more mobs, better for geared people.
3rd lvl: only like 30? but easier for weaker people to handle. Only problem is GETTING to the third level.