Baldur's Gate : The Sword Coast Chronicles : NWN2 Persistent World

I've noticed some mobs are now using a spider form (Xvarts but also the boss in the goblin cave) .
Their AC appears to be a bit on the high side (got blind fight)

I've tested it out by fighting the boss in the goblin cave for about 4 minutes long.
Level 13 with AB 20-15-10 back there ,rarely could I actually land a blow.
While mobs of much higher level proof no issue in terms of hits.

This is coming from a melee fighter build.

Previous I ran the place with 2 nabassu with an AC of 38 and AB of 33 (buffed) even than the spider form proofed to be an issue in terms of landing a blow.
Given That PC was 15 or 16 but still.

Is this intended?

The dynamic CR system gave them the plant shape feat, and the wildshape script had a bug that when treant shape was used by an NPC, it actually used the phase spider shape from magical beast shapes. That's an epic shape so no wonder you guys had trouble fighting that. Fixed at next update.