Here are some ideas for improving in and/or warnings about some of Riijas spells.

Level 1
Anonymity -- You get no protection from Shal'ille while anon, meaning anyone can attack you without any repercussions.  So it can be used for working with another person who is casting and improving offensive spells as well.

Blink --  If you blink in the Riija temple you will find yourself in the middle of the Island City of Kocatan. (Also if you log or lsc while in temple or on the temple side of bridge.  If you have a mule who you plan on leaving at temple who is Riija, make sure you log them on the other side of the bridge.)

Feign Death --  You will most likely drop item(s) from your inventory.  This spell will get you out of morph form.  So might be an option to work it while working Morph as long as you are in a safe place where people aren't going to be looting the items you drop.

Shadow Form -- Cast this whenever moving through a screen with creatures.  Sometimes they don't notice you.  Sometimes.

Level 2
Bait --  Bait is a very nice spell if you want every mob on the screen drooling for the chance to take a swipe at you.  However, it is not very nice to use this spell if others are fighting on the same screen.  Even if they are fighting where the creatures are going (towards the baiter) they don't get hit and they don't get experience, or at least not much if any at all.

Foresight --  This spell seems to improve better on good karma chars.

Level 3
Illusionary Firewall -- This spell works great in tandem with Bait.  Bait all the mobs over to you and then, (If at all possible depending on which screen you are on), carefully make your way out to the furthest point the mobs stand while drooling all over themselves to get to you and Firewall.  Move back a couple of feet and Firewall again.   Then move to the closest point where they stand and Firewall right on that spot.
I call this staggering the firewalls and it works great.  By the time they are in front of you one hit will finish them off nicely.   
(Illusionary firewall will only take a mob to 1 hit point.  You have to finish the job.)

Level 4
Apparition -- You can use this spell just about anywhere.  With a low hit point character I usually do it right outside guard tower.  Target a mob and cast.   Takes a lot of vigor and mana so it's nice to have a relay mule/char helping you.   Or even as a second char just logged on, just go thru mana and work on a second char while waiting for mana.
Denial
--  Go up to one of the avars there and let him hit you once.  If you are 20 hps make sure you are ready to back up quickly after the first hit.
Then cast denial.  Denial doesn't take much vigor or mana so you can work this in between the apparitions.

Dement
--  If you are a low level character chances are you won't even get this spell til later when you can make a trip to the ML since you get it from Afiera D'xor.  Say "Pupil" to him and he will give you some item to deliver.
Be prepared to take a token death afterward though because you get a really nice myst or intel effect.  Can't remember which.  According to sources you can cast this on any mob.

Level 5

Artifice
-- This spell you can cast on anything... once. Til the illusionary effect wears off the item. (The effect is only an illusion.  The item will not have the magical properties.)
However, if you cast on stackables and then put them back into a stack, it returns to its non illusioned state.   What I usually do is lay out a row of fern or shills, cast on them all..and then pick them all up and repeat.

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I have left out Morph and Elusion along with a few others I really haven't worked much  since just about everyone knows how to Imp these and if not see my main page under
"Its Morphin Time" for more info on Imping Morph.
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