Dark Omen pillars 

1. Immersive battles
   slow-paced with focus on tactical maneuvering and micro-management of moderate-sized troops rather than grand armies confrontation, button mashing power-ups (e.g. strength boost), "alive" units (talking portraits)
   
   
2. Tabletop rules adherence (which emphasizes medieval warfare simulation)
   combined arms, formations, flanking, line of sight, terrain advantage, troops morale, etc
   
   
3. High fantasy setting 
   mythic races, terrifying monsters, powerful sorcery and artefacts

It is porbably worth to mention also engaging storyline in Dark Omen single-player game mode as well as music and sfx which helps to pass tense of battle

features prioritization example by using pillars: