Strengths
- They are excellent for taking out enemy cavalry, if they win instant dismount and S3 hit.
- Good for taking out spear supports
- They can also be good be objective grabbing. Heroic combat can potentially take you 24" in one turn (and a heroic movement next turn will take you 12" further away)
Weakness
- With only a FV of 5 if an untransfixed hero gets into combat then you can find that the Fellbeast will lose combat (unless you have a combat wraith)
- As you mentioned they are susceptible to shooting.
- The large base means that they can get trapped easily.
Thats my input
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