Morgana's abilities are dependent on each other and can cause a lot of damage really quick. With some cooldown reduction and landing your skillshot, your opponent should never be able to run.

Soul Siphon This is Morgana's passive ability that grants more spell vamp as you level up. Its like a passive lifesteal for spells.

Dark Binding, snares the enemy and does a decent amount of damage. This is a very good combo with the tormented soil because you can snare and then put the soil under the champion.

Tormented Soil, is a circle area that when casted causes enemies that are on the area damage and reduces their magic resistance. During any point of the game this can be used to farm minions. Early game farming isn't the smartest idea because it will drain your mana fast.

Black Sheild, blocks spell damage. This can change the outcome of a battle. Shrewd use of this is very important late in the game because it can block that team battle initiating stun or snare. Also the more Ability Power you have the more spell damage it blocks. Its very useful against teams with a lot of spellcasters.

Soul Shackles, a multi-target mass damage dealing stun. It can only be used within a certain distance of the enemies. When used it does initial damage and then channels for four seconds then does the same amount of damage and stuns to the enemies within the area.

Flash very useful for getting in and out of battles quickly. Can be used in with the combo of the hourglass and your ult.

Ignite very useful for that last bit of health that an early game champions so that you can gain stacks on your soul stealer.

Early game Morgana is very important, she is good at burning enemy health slowly. Early game it is important to get kills and assists so that the stacks on your soul stealer start to build up. Don't use your tormented soil to farm minions right away, place it so that the caster minions are on the front edge of the circle so that it still does damage to the minions but spaces out the enemy champions so that they gain less experience or loose health. If you can land a snare on them to keep them on the soil, it is a great way to quickly deplete early game health.

When going into a small battle where you can see all of your enemies on the map and start out with the snare and tormented soil then immediately soul shackle afterwords so that after the snare is done the channeling will be done and the stun will have hit. By this time with the cooldown on the snare should be done and if your enemy is still alive you can snare him again. This making it very hard for your enemy to get away. You can throw an ignite in there somewhere if you wish.

In team battles you can initiate with a well landed snare or you can wait for someone else to initiate. Once the battle is initiated, flash in, cast your alt, and then use your zhonya's hourglass. Thus turning you untargetable for the next two seconds giving your ult a good amount of time to channel. You will be right in the middle of them and they won't know what to do and then you stun them and deal damage.

The soul stealer is not essential but is very helpful if you find yourself stealing kills early game. When going back to the base to buy items, if you have enough to strait up buy the soul stealer, buy it before the boots. If you don't get a lot of early game kills go for the catalyst the protector and then the boots.

The sorcerer's shoes can be traded out with the ionian boots of lucidity for a little more cdr or mercury's treads if the other team has alot of stuns and snares.

The rod of ages is very important to a Morgana build. It is in almost every build you find online. It gives you alot of extra health, mana, and a decent amount of ability power.

The hourglass is a also important because it grants 100 ability power and has the two seconds of stasis.

The deathcap is where all of your power is going to come from. Once you get this depending on if you have alot of soul stealer stacks, you will be doing a large amount of spell damage.

The last item can be intermixed with several other items. I like to go for deathfire grasp because it grants cooldown reduction, ability power, and has an active that does 30% of the target hero's current health plus a little more depending on ability power.

If you decide to buy the ionian boots instead of the the sorcerers shoes you will not need the cooldown from the deathfire grasp so as a replacement item buy a Rylai's Crystal Scepter for extra health and ability power. This will also make it harder for your enemy to get away because it slows the enemies movement speed when you do spell damage. This is a good combo with the tormented soil because if an enemy is running away you can place it in their path and they with take edition damage along with being slowed.

Another item that can replace the deathfire grasp is the will of the ancients, it gives ability power and has a spell vamp and ability power aura. This just makes you able to regain more health when you land a spell.