I've edited my post. As per Cameron, the Warp Energy is spewing from the broken seal. As a result, Soul Reaver's spell has manifested differently - it's been cast not on the tower, but on Abaddon, and is much smaller.
- Being considerably smaller, it's more concentrated and harder to break
- It's only blocking the warp energy that Abaddon has been absorbing. Other things will pass through just fine in both directions including spells and physical objects. Its surface rejects Warp energy violently though, including raw warp energy inside other things.
- It will travel with Abaddon and its size (and shape if necessary) will adjust according to his own. Trying to teleport will teleport the shield as well, and trying to teleport 'into' a source of warp energy will result in the barrier displacing either the warp energy source and/or the teleportee at the instant of arrival to keep them apart (possibly with physically violent outcomes).
- Because the barrier is now on a sentient, mobile being rather than an inanimate location, Soul Reaver requires more focus to keep it in place. He's taken a more defensive stance in preparation.