The Watchers will return

Deck Focus:.............Beatdown with Frostguard Thrall or win through Watcher.

Deck style:................Control

Format:.....................Standard

Period:.......................Empires of the Ascended >

Cause of death:.......Not yet

Recent Changes:

Core:

Frozen Thrall x3
Draklorn Inquisitor x3
Lissandra x3

Advance:

Clockwork Curator x3
The Clock Hand x2

Staples and techs:

Shaped Stone x3
Scrying Sands x3
Avalanche x3
Ancient Hourglass x2 - Combo potential and protection.
Three Sisters x3 - Three in one: flexibility at the cost of one more mana.

Aspiring Chronomancer x3 - pseudo-draw and early drop
Kindly Tavernkeeper x2 - heal and early drop
Soothsayer x2 - Protects Frozen Thralls as well as Lissandra.
Desert Naturalist x2 - Landmark removal and can spawn Grumpy Rockbear in a pinch.
Trundle x3 - Can behold Frostguard Thralls and spawn an Ice Pillar for a free 8-cost.

Cards that can be added depending on flavor:

Succumb to the Cold - Flash Freeze and a Frozen Thrall in one card.
Wyrding Stones  - Allows turn 4 Trundle and Draklorn Inquisitor.
Ancient Preparations - Early drop and predict.
Rite of Calling, Entreat - tutor for Lissandra
It That Stares - AoE, 8-drop and landmark removal. Deletes Frozen Thralls though.
Promising Future - Combo with Frozen Thrall and Entomb, but a bit too slow.
Buried in Ice - unique board clear in that it freezes the board for two turns. Works as a finisher, but might be too slow.

Techs:

Ice Shard, Avalanche, Spirit Fire, Blighted Ravine - AoE
Kindly Tavernkeeper, Catalyst of Aeons, Revitalizing Roar - heals
Rite of Negation - deny
Weight of Judgment - removal

Alternative builds with different focus: