Yakchal

The Ice Witches Boss, talked about in this book.

Note that she did not disappear after 45 minutes after the awakening!

Attacks from a distance. Yakchal will retreat at 1 to 229 (0.02% - 3.98%, deep red) health.

If you are using a blocker, they should stay near the Sarcophagus when it gets summoned, and will need to use a lot of Great Health Potions. The shooters should be spread out through the room, and should use SD runes on Yakchal. Be careful when waking her, because you will also wake up a huge number of Ice Witches, Ice Golems, Crystal Spiders and Frost Dragons. (In four 'waves', approximately 6-8 Frost Dragons, 10~ Crystal Spiders, 15~ Ice Witches, 20-30 Ice Golems and the Yakchal will spawn in only the south of the room! More monsters, mainly Ice Golems and Crystal Spiders, will spawn in the west, north and east in the room.) Those creatures will not all come at the same time.

Dying by Yakchal's summons on a 140+ master sorcerer.

One strategy is to use the south-east corner of the room as a retreat-point when a lot of monsters are summoned. First make sure to kill all the summons, then trap Yakchal with an Energy Bomb Rune, so she won't move. Then finish her off with SD:s. Another strategy is having 1 person awaken her, and then rush to the south doors. Use a Frozen Starlight on the sarcophagus to awaken her (The Frozen Starlight can break when it's used on the sarcophagus to awake the Yakchal, but usually it won't. You can awaken Yakchal many times, but the delay between awakenings is random.

To be compared with:

Make sure somebody blocks respawn on the other side, otherwise there could be a Demon, Plaguesmiths and Nightmares. If you're fast enough, you won't have to go to the other side of the door to be safe from the most of the creatures that will spawn with the awakening. From those doors, you can then slowly lure all creatures one by one, and sooner or later Yakchal will come too. Unless your team has a lot of firepower, try to trap her in a corner somewhere, she will run away in very low health. Shoot at her with Sudden Death runes and/or Assassin Stars.