My Dragon Fury: Spear skill is at Level 30: (Use 30 HP, 20 MP, Damage 250%). However, the damage is incorrect, It can only hit around 5k to 8k damage. Another of my skill, Power Strike (Level 16: MP -10; sword damage 240%) can hit 9k+ damage. I think there is a bug about Dragon Fury. My range: 2282-5990
This is normal because spear using different multipliers when you swing/stub. You see 9+k damage because you stub
Spear and Polearm have different calculations depending on the attack that occurs. Spears have a higher mutliplier when stabbing and polearms have it when slashing. When you use Fury with a spear, you are guaranteeing a slash attack, which spears aren't used for. This is why most guides recommend going hybrid, as to also make use of polearms to use Fury with instead. Slash blast randomises between stab and slash, which is why you will get the higher damage on the stab motion. What you should be comparing is the damage when the spear slashes.