Cloth when facing AD enemies, its invaluable to have armor against AD enemies because it mitigates a big portion of their damage. Flask is the to-go build for anyone else. It gives you a lot of sustain and mana in lane and once you go back it refills, meaning you wont need to buy HP pots every time you back. As long as you use all its charges every time you go to the lane, after ~7 refills it becomes cost effective (meaning you saved enough gold from getting it instead of HP pots) and can be sold. Its a solid start because it means you can out sustain your enemy in the lane and push him out of it.
Getting a ward is good if the enemy jungler is
, and generally a jungler who can disrupt your
and wont have problems dealing with your root.
Practically this is a good start for an item build, instead of Liandry's you're building Zhonya's. This is generally good for when facing high AD teams and when you have bought a quick Armguard. Zhonya's on top of your ultimate gives you a huge grace period. A good tactic with Zhonya's is to go in with
, use it, Zhonya's, and when its runs out use
. This way you can bait several abilities from the enemy (think Misaya's TF Destiny>Gate>Zhonya), and get a nearly guaranteed teamfight.
This core is good against high AD teams, and when they dont have lots of tankyness.
Doran's Rings are very good early game on any mana AP Mid. Lissandra is no exception. She can use the mana regen, AP, and HP very well in order to assert lane dominance.
Sorc Shoes are the best choice for Lissandra, since she has good base damages, and Mpen is very strong on her. The only alternative is
, which should be bought if you are against AD and you lose your lane, or the enemy is FULL ad (Ad top, Ad mid, Ad Jungler).
is invaluable, since it turns your boots into semi-mobility boots, so you get faster to your lane, or go faster to lanes that you want to gank.
Liandry's is great on Lissandra because every spells minus her
has CC. That means that it does its full extra damage. For that reason, its a very worthile pickup, even if your spells are AoE. Also HP and Mpen are GREAT on Lissandra because of her low range.
In general this core is good for when facing tanky teams.
You want some CDR in general, go Morrellonomicon or Athene's are a must for Lissandra. Morrello is better cost efficient wise, but Athene's is great against hard matchups.
Finally you should get Armguard if you face an AD mid, because its insanely cost effective agains them.
good when facing double AP (Ap mid + Ap jungler or Top). Very cost effective and its aura is always used because you are a close range mage.
this is strong on Lissandra because she can use the CDR greatly, and her AA animation is great. Its a good item for when facing a lot of AD enemies.
is one of the BEST items, and generally my second pickup. It gives a LOT of CDR and a good amount of AP, but most of all, its really cheap and really cost effective. If a game is going smoothly this is going to be my second item for sure.
Rabadon's is the standard item for pumping your AP, I dont think it needs any introduction, its a good item to snowball games if you get it early, but thats very risky. The more AP you got the more cost effective it gets, so keep that in mind. You should strive to get a Rabadon's at some point in the game, but when is up to you. If you want more PURE damage, Rabadon's is the way.
is another item that needs no intro. Its just something you will need at some point, a good rule of thumb is to buy Void after 2 or more enemies have more than 100 MR. They have up to 100 MR HG and Sorcs are kind of enough.
is ok, because its probably the best item for HP. Good AP, good HP, the extra slow isnt really needed, but its ok. Get it if you want more health.
is very strong if you are going for objective rush and you want to catch someone off. If they are slowed they wont escape your combos and die. Its good, but not that great, situational pickup, cant fit it anywhere really, but should be mentioned.
is also VERY strong, because it gives a LOT of AP, and lets you have more invulnerable time, on top of your ultimate. Very strong against have AD team, should be picked up almost every game if you feel like you're getting nuked, or if the enemy has high AoE champs, like
is a good alt to Morrellonomicon against heavy AP teams or very hard lanes, such as Kassadin or LeBlanc.
is amazingly good, atleast on paper. Seraph's is an amazing powerboost, because it gives a big AP bump, and an amazing shield. Its ridiculously cost efficient, and you can just get Tear, and then wait until much later on to upgrade it to Seraph. TPA's Toyz has deemed this item as "the most OP AP s3 item", and thats because its so cost efficient, work on every mage, and simply gives so much, nearly endless mana, mana rege, huge ap, and a shield on top of that. It also fits every build since as I said, Tear can be bought early, and be upgraded only when needed later on, so it hardly inhibits your ability to buy other items.