i play morgana alot, and have found a build that fits my play-style
if you dont go for the despfire-grass thing, but go for zonias hourglas, you got armor, and 40 more AP
void staf? you got enouf magic pen with soccer shoos, and abysial scepter, go for somthing like mejas soul stealer (whitch also give cooldown if 20 stacks) or ryias (that give you 500 hp, 10 more AP, and your turnament soil slows
i play with this build:
dorans ring (sell laiter)
soccerboots
meias soulstealer
rabandons
abbysial scepter
zoniaz hourglad
and rylia scepter

also i dont use 2 mastery point on death-time, and gold grail, but insted get a 9-12 bonus moovemtspeed

my machhistory (with morgana):
9|1|14
6|4|20
3|1|3 (short game)
13|0|12 (co-op, so it dont count i guess)
21|1|21
4|0|4
1|0|11
11|1|14
7|2|20
11|3|26

i play morgana alot, and have found a build that fits my play-style
if you dont go for the despfire-grass thing, but go for zonias hourglas, you got armor, and 40 more AP
void staf? you got enouf magic pen with soccer shoos, and abysial scepter, go for somthing like mejas soul stealer (whitch also give cooldown if 20 stacks) or ryias (that give you 500 hp, 10 more AP, and your turnament soil slows
i play with this build:
dorans ring (sell laiter)
soccerboots
meias soulstealer
rabandons
abbysial scepter
zoniaz hourglad
and rylia scepter

also i dont use 2 mastery point on death-time, and gold grail, but insted get a 9-12 bonus moovemtspeed

my machhistory (with morgana):
9|1|14
6|4|20
3|1|3 (short game)
13|0|12 (co-op, so it dont count i guess)
21|1|21
4|0|4
1|0|11
11|1|14
7|2|20
11|3|26

Dear friend,
I would appreciate seeing a build that does everything you said better than mine like you said. A link perhaps?
I must say i believe any build with more mana than this is wasting money on the item bringing it, and would affect others aspects. I never run oom at high lvl and believe getting more would lower other more important stats.
I do sacrifice movement speed, as i do not jungle much and rely on a safe kind of play, which i believe i more appropriate for Morg's role.
I also think you did not take in consideration the 30% AP boost from the deathcap, which does not appear in the stat overview at the beginning of the build. Brings me over 450 AP, which is more than enough to kill.
I recommend that you try my build before you say it is not ''viable''; as it is, i've been playing with it for a while and have really good results.
All this said in a constructive way,
Deity

You have super magic pen but almost no defense. With your build morg is very squishy and slow. also you don't have that much ability power and despite your mana regen i feel that you could run low on mana in an extended fight.

i have seen morg builds that are faster, tougher, have more mana and dela more damage.
I just don't think you build is that viable.