This is a peasant (only commons and uncommons, no campaign cards) mono shadow deck for Expedition. If you have good rares (like Impending Doom or Marionette Cross) you can swap some of the other cards out (Impending Doom can replace Darkmask Stalkers, Argenport Instigator can replace some Dark Wisps or Devours, Marionette Cross can replace Thornbeast). This is mostly made for the new streamer wymsic, but of course everyone is welcome to try it.
Its a midrange deck that tries to apply pressure from turn 2 or 3 on and tries to close out the game at around turn 7 or 8. The best cards for your starting hand are Prism Golem, Marionette cross (if you have it) and Thornbeast (if you have a cheap unit to sacrifice, like Wisp or Slumbering Stone). You try to have around 3 power in your starting hand (Etchings can count as 1), but it can vary depending on the cards in your hand (Spiritweaver can count as a power because of plunder; if you have enough card draw or are going second you can sometimes keep 2 power hands too; 4 power hands are fine with some 4 or 5 cost units, card draw or Etchings). Some removal (Suffocate or Defile for smaller stuff, Annihilate and Devouring Shadow for bigger stuff) is also good.
The deck has a lot of internal sinergy: Devour and Ravenous Thornbeast are great with all smaller units, especially the ones with entomb or corrupted. Mightweaver allows you to race opponents with all your 5 attack units (Prism Golem, Feartracker, Thornbeast if you sacrificed something) and Feartracker heals 6 instead of 3. Entranced cultist makes them harder to block, especially if you bring them back with the market copy of Triumphant Return. Removal spells and Two Face can buff the Darkmask Stalker.
The market is mostly there to get some reach in the mid- to lategame. Murky Tentaclesis can provide some nice tempo because of unblockable, but is bad if you are behind. Lighthoof can close out games or provide tempo in a similar, but more immediate way. Triumphant Return is a nice pickup to get more value, especially if you have a Feartracker in the Void. Deathstrike is the general removal spell if you need to get rid of something and Defile is there if you need a cheaper option for smaller stuff.
Good luck and have fun!