Your win condition revolves around:
- Find either Shield Mentalist or Summoner Mentalist
- Attach to castle
- Find Circle of Mentalists
- Bomb the outsider and/or portal for 10 damage
Early game you need to survive and control the board, especially minions. Use spells to take favourable trades, and cards like Clan of the Wildcat and Frostbite Outpost to stall monsters.