What you need is the Mythical Items Pack. This includes ALL of the previous item packs plus other individual packs. You can download the installer
here. (It is in Brazilian, but it provides English instruction. So far, I have had no missing texture issues!
Take heed to the fact that the items.cfg must be updated along with the mythical pack, since everything is completely reordered. So you, will need to copy and paste this straight into the items.cfg file. Select all the current text and paste over it, to make sure there are no repeats.
This also provides the labels of each section, so you know where to find everything! (I think this adds on to the Legendary pack, so you may not have an issue there).
I hope I've helped!
Other Notes:
Ulquorria's horns are white with light purple stripes, seen
here.