To kill Kylikki either solo, or in a small group for easy Tier 1 epics can be a rather complicated and long exploit for you. A Tempest of Set is needed for groups, otherwise rogues with the feat Cheat the Reaper can solo her.

As you enter Kylikki's Crypt, which is located in North-East Field of the Dead, you need to walk through the wall to your left. This is easily achieved if you have more than one person. While you are stealthed next to the wall, have someone stand behind you; when you unstealth, you should get pushed through the wall. This may take a few attempts to achieve.

If you are soloing or you happen to be the last person in the group, you can get through the wall by yourself by spamming jump at certain locations in the wall. It will take you sometime to master, but is easy once you manage it a few times.

When you walk through the wall, keep going until you fall "through the world", and die below the instance. Here is where a Tempest of Set is needed - have him apply Spark of Set on himself before he walks through, and then self-res when he hits the bottom, and then resurrect the group.

When everyone is down below, proceed to walk North-East until you see mobs above you. Rangers can track to make locating the mobs easier. Now follow the mobs north until you reach Kylikki herself at this point the ground should be just above your head.
You will notice there are 6 mobs that patrol around the room. These mobs won't attack you, except Spellguards which will bug below the ground. They won't be able to move, and they can't nuke you, but they will occasionally cast a small Area of Effect which does roughly 1500 damage, and sometimes teleport to the group. They won't be a problem if your group just moves away from them when they teleport, but you may wish to kill them (from range) anyway as they have a ~10% chance to drop Tier 1 Shoulders, Boots and Belt.

You cannot directly nuke Kylikki herself due to line of sight so to kill her: Classes with Area of Effect spells can AoE her through the ground, Necromancers and Demonologists can attack her with pets, and Melee classes can attack her by swinging  at her while jumping (you get the hang of it after a while.

Kylikki drops Tier 1 Chest and Bracers, and her adds have a chance to drop Tier 1 Shoulders, Boots and Belt, if you wish to take the time to kill them.