Is Darth Sion incredibly bad or is it just my experience?

I'm so disappointed with Darth Sion, I think his kit is really weak. He literally does no damage, and I mean other tanks have no damage but they at least bring buffs to their team. Sion doesn't.

I have him at 3 stars gear 10 and 199 speed with defense triangle, protection circle, speed arrow and tenacity cross. His speed is at 199.

I'm not expecting him to hit like a truck but even his special when they have pain is weak, nothing even close to the video of his release.

I run him under palpatine lead(zeta) and the battle never goes long enough to pop his special. I ran him with palpatine, Vader, nihilus and thrawn then I realized I needed another tank so I put Kenobi instead of thrawn. The results aren't very different.

I understand that his star and gear level are low but he never gets his special off and his high damage ability does way less than expected.

I don't know what his purpose in the game is but he doesn't seem very good in arena to be honest