Playing as Sleeper
Your Faction is not particularly interested in combat. Instead, your Units debilitate your foes outside of Battle. You are not the quickest Faction to gain the lead, but you can be lethally and viciously petty.
Try to build up your Power base in the early game. Summon cheap Monsters in the first Action Phase, so that you can start to spawn better ones via Death From Below. Do not discount the usefulness of Cursed Slumber, especially in the early game. You have a Spellbook requirement that gives another player 3 Power—use this to bribe or bully your opponents into doing your will.
In the late game, ability accumulation bears grim fruit for your foes. With Tsathoggua on the Map, you can spend Action after Action in Lethargy. If your foes don’t react you’ll be the last player left with any Power, and you can use it to march Tsathoggua (cheaply, using Burrow) to Capture Monsters. Even though Tsathoggua’s Combat is reduced late in the Action Phase, a couple of Formless Spawn let you inflict Kills. Demand Sacrifice either protects you from retribution or makes your opponents pay for their attacks against you. If you Move with a Wizard, you can use Energy Nexus to run away before any fight.
There are too many choices to list them all. To name just one possibility: copy Cthulhu’s Faction ability to replace a dead Tsathoggua on the cheap (and earn an Elder Sign!).
Spectacularly useful. Doubled up with Lethargy, you can save Power like crazy.
The advantages are clear, even for the most inexperienced player.
Gives you a smaller footprint on the Map, and you can reverse it to teleport a Gate anywhere on the Map. Then, Cursed Slumber a new Gate from your home base and set up a Gate factory.
They’ll spend the Doom when facing Tsathoggua, but otherwise you can act with impunity.
This Spellbook has SO many different ramifications and possibilities that we can’t list them all! Here are just two possibilities: use Cursed Slumber to Move a threatened Gate off-map, or use it to fulfill one of Sleeper’s Spellbook requirements and immediately gain the Demand Sacrifice Spellbook to use in the following Battle!
Sleeper is weak in Battle until he has two or more Formless Spawn out; take advantage of his early weakness. Unfortunately, Demand Sacrifice makes him hard to Kill. Sometimes you just have to suck up the pain of giving him an extra Elder Sign. To suppress Sleeper, take Actions that force him to spend Power and lose his late-turn advantage. For instance—Killing two Formless Spawn will cost him six Power to restore. Of course, Killing Tsathoggua is always a treat. Without giving him an Elder Sign, you can Eliminate his Cultists outside of Battle (using Dreams, Zingaya, or just plain Capture). He usually does not have many Gates, and they are often ill-protected, so it is effective to strike at his Gates. Even if you can’t Kill him, you can Pain him away.
Sleeper gets the equivalent of a two-to-three Power boost every turn via his free Monster from Death From Below. Do not forget this.