I'm beginning a new character, and I really want to try and RP a robes only mage/assassin. I'm thinking that alteration/destruction//illusion will be my primaries, with one hand, enchanting, and sneak as 2nd tier. No bound dagger (don't have Dragonborn) so smithing may be important as well but I don't want to spread myself too thin. Any other suggestions? This is my second character, my first was a light armor/stealth assassin that is fun but getting stale so I wanted to change it up a bit. Merry Christmas!

What about conjuration? bound bow Makes for good stealth kills and such.

You can also fill up soul gems for your enchanting

Merry Christmas to you as well!.

Conjuration is AMAZING for Nightblades (the term generally used for Magic thieves/assassins in TES). Summon something to distract the enemy (use the silent casting perk from illusion to make sure they do not hear you) then snipe.backstab them one by one while they are busy with a big, angry Dremora.

I would choose Destruction OR archery to put perks in since they would fill similar roles (long range damage) though having a bow on hand at all times might be helpful just in case. Flipside is Frost magic slows the target down so even if they DO notice you, they will have a hard time getting to you.

Illusion is IMO, almost a must for a magic-based assassin, invisibility, silent casting, etc are all so yummy with sneaking around.

Didn't even think about conjuration, a "make your own meat shield" department, so a must! I was planning on forgoing archery and relying on destruction for range attacks, but that may change if I'm too squishy at first and/or running low on Magika. Illusion will definitely be a star with this guy, loved it with my first character.

You should do fine with destruction, illusion, one handed, and sneak. Since you can get the dark brotherhood ger at level 1 you will be kicking ass from the get go. No need for smithing, you will have 50 sneak and x30 damage within a few hours just by killing sleeping draugur with your dagger. With a decent unsmithed dagger or the blade of woe you can instakill the vast majority of enemies with a sneak attack. Use slow time to get multiple sneak attacks in against stronger enemies. Silent casting seems to work good for me with destruction spells. Even when dual casting fireballs from Sneak enemies seem to take a long time to locate me. I agree with previous poster pick archery or destruction but not both.

with quiet casting you can easily conjure a bound sword and slit someone's throat. Hits pretty hard without smithing. Enchanting 1h damage and x6 damage from sneaking can provide some big hits.