^Title I don't want to devote more than one slot to a mana item, be it mana or mana regen. I'm tired of going oom and having to back in the late game after a teamfight even when I'm full hp, just because I'm not a resource-less champion.
This is subjective based on the champion and role you are playing in. Are you asking for mages, ranged carry, bruiser, tank, or what?
In tune with the cdr it also gives
Health for increased survivability, increased mana pool is just harder to burn through in general
For AD Casters
Tanks who also want cdr
what champion are you playing? usually super high mana cost champs take tear, chalice, or roa (if they need tankiness). assassins like ahri usually take a morello
For mana regen, I generally always take Athene's. That bit of MR is waves better than the 20 AP and grievous wounds on Morrelo's I'm not really sure on just mana though, as the only champs that I play that really need just more mana are tanks (so Frozen heart and a RoA on my Naut)
maybe a thought outside the box for you: perhaps a support whos willing to use summoner spell "clarity"
or maybe you take clarity. theres always a way to make your champ work. good luck
Personally I go Athene's on almost Every ranged AP....this is due to the CDR and the PASSIVE...it is GOD.
in a 5v5 it's Unlimited mana if you stay alive and continue to participate in the fight.
I've never seen the benefit to over 
. Usually the people I build these on are long range casters who shouldn't be taking damage anyway.
This is a very arbitrary question.. Which champion are you playing?
For example, if you're playing TF, the only mana item you need is 
, but if you're playing Anivia you're probably gonna want AND 
, and if you're playing Urgot or Jayce you're gonna be looking at 
.
If you're playing a champion that needs mana regen, obviously you have 2 choices. or . I typically don't play any champs that need mana regen outside of Anivia (who builds a lot of flat mana instead anyways). I think the general decision to make here is "how much do I want to spam my abilities?" and "Am I fighting a Swain?" Basically, both are good but one is better than the other in certain situations. Morello's higher ap and grievous wounds make it relevant in any match though, but I'm thinking Xerath and Sona and such would prefer Athenes.
Depends on what champion. Tanks just use . Also take the consume mastery since you get 6 mana back if you manage to get all the creeps in one wave.
I am surprised no one as mentioned .
Although I rarely play mid, so I can't really give much insight into this.
