I ignorantly chose that as one of my 7 major skills when I first created my Khajit. I like my character and all but I feel that that the trait is pretty expendable. Are there any Illusion spells that will rectify my poor decision? .. I really should of chosen light armor as one of my major skills.. bah...

I guess it depends on what the rest of your skills are.

If I am building a stealthy character, however, Illusion is typically a "must have" for me. Sneak is very good when in shadows and the like, but Invisibility gives you a lot more flexibility, and combined with a good Sneak skill you can wreak havok on your foes.

Actually, the real question is whether it's useless to have the Shadow sign if you have Illusion as a major. I would say yes. Consider restarting with a different sign and Illusion as a major. Once a day invisibility is not worth much; you can get it free from a rune stone or unlimited from a spell.

I'm already level 9 and I really like the character, I've actually played him for 20 hours already!

Well, I would say keep going and make the best of it, birthsigns don't mean much after the first 10 levels anyway. (unless you're a mage and need the extra magicka from mage or atronach) Don't let the fact that the Shadow benefits will be wasted stop you from developing Illusion; it has a lot to offer to a stealth character.

Well one thing having both will do is allow you to have access to the Inviso effect before your Illusion skill gets to 50. Illusion is not a waste. Get spell making, then make something like this....

Command Creature/Hummanoid (your level +5) for 4 secs (all you need is a short duration because once they start fighting they will go past the duration).
Optional added effect (inviso on self for 4 secs to get yourself out of the way).

Sneak up or walk up invisibly and cast these spells in rooms with multiple opponents, get some popcorn, watch the show, then backstab the last one standing with a poison dagger.....loot, etc.....

Lol. I have a spell called Party Time! which involves frenzy and invisibility on self.

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