I go - "Your pain will be legendary"
OR
"I'll soak my beard in your blood"
OR
"DILBARDAGA!!!" (no idea what it means, picked it up from the vikings race in Age of Empires II)
Not really Battle cries but things I say instead of a battle cry
You are weak. Begone!
You're in the way...so move!
If you want to see hell so badly... then I'll bring it right to you!