Vel'Koz + Luden's Echo

Double dorans will sustain Vel Koz. His mana costs are non existant

im not a vel player since i cant afford him yet, but i would think he would encounter mana issues if he went luden's first

Athene's -> Luden's is probably the best way to go Vel'koz mid.

Vel has good base damage and mediocre scaling, so getting Magic Pen is more important on him than Ludens. Get Sorc shoes and mana regen item, then see, if the enemy has got MR items - if they have, get Void Staff, if not - Rabadon. The next 2 items are situational.

No the item sucks on Vel. I played a bunch of game with Vel yesterday trying different starting builds and stuff.

MPEN is the way to go

Luden's Echo is a good first item on any mage ever.

That being said, I'd either grab a pair of Doran's Rings or an early Forbidden Idol just for the mana regen to start out with before building the magic beatstick.

I would say it is better as a second item. You want the CDR and mana regen of Athene's or Morello's for mid Vel as you will be throwing out abilities a lot on him. It's (Luden's Echo) pretty good on him because his AP scaling is pretty low and this will basically add to your damage output with more static numbers.

(if enemies are building MR) can be a potent build order. Finishing up haunting guise into Liandry's later in the game. I would probably only get Luden's if you are winning pretty handily though as later in the game, Deathcap will still out damage Luden's.