Downstairs Master Rixiz has the third Rank skullcap.

                   Thanks to Shilarva of Fennin Ro for submitting information
                   on the third skullcap:

                   To complete the quest you need a sarnak crypt raider brain,
                   which is a lvl 10-11 spawn that come up along the lake of
                   ill omen, and embalming fluid.

                   The kicker is:  a) you can not DIE while holding the brain.
                   (if you get any brains, and die, you lose it,unless its in
                   bank.  Its not NO RENT, it doesnt say it on there, but I've
                   lost a brain every time I died.)  b) embalming fluid had
                   never been made before, and there were two recipes on how to
                   make the stuff needed for the fluid.

                   To make embalming fluid you need:

                   1 rubbing alcohol. 1 bone granite powder and 2 bog juices.
                   a amauter brewer should be able to make it.

                   You ask the mortician how to make bone granite powder he
                   says:  as it sounds, 2 of one, a pile of the other, hammered
                   in heat until it is one.

                   Translation: Combine 2 Bones (seperately), the Granite
                   Pebble
                   and a Forge Hammer (bought at the warrior guild merchant
                   next to the forge) and combine in a Forge.

                   If you ask the alchemist NPC how to make bone granite
                   powder. (see other quest on bone granite powder) he says:
                   using you skill of alchemy, combined three piles of bones
                   from decaying skeletons, and 1 pile of granite pebbles.

                   Now...no one has made the bone granite powder....but I
                   finally got it done.  The hard part is to get the granite
                   pebbles.  You need two froglok escapee shackles.  With a
                   skill of 20 in smithing, I made the powder on my first try.
                   It said it was trivial, but when i messed up and lost the
                   powder it took me three more tries to make it.  The bone
                   granite powder *IS* NO DROP, NO RENT, LORE.

                   Because the bone granite powder is no rent we must recommend
                   that you have your blacksmithy and brewing to 20 or more
                   before creating it as you do not wish to lose all the work
                   you have put into it.

                   Anyway, combining JUST the rubbing alcohol, 2 bog juices and
                   the powder, it gives you a sack of embalming fluid.   The
                   good thing is if you fail, you dont lose the bone granite
                   powder. (in case you were wondering) but you lose everything
                   else.

                   Combining the fluid and a sarnak crypt raider brain in the
                   canopic jar, it formed the preserved sarnak brain I am
                   sending you....handing over the 2nd rank cap and the jar
                   gave me the third rank cap I am sending also.   The third
                   picture is how the iksar look wearing the cap.   As a side
                   note: you can hand in JUST the jar, and then the cap, or
                   vice versa and still get it, or both at once.