Xerath Ability (LoL): Mana Surge

A base necessity in early play, that falls out of use in later play. More essential than useful. Always have this triggered when you can in the early game, and land attacks on champions when safe to do so, as rare as it is, usually near tower for the the double amount.

The new passive is incredibly lazy. Second only to Martial Cadence.

Prob my favorite passive. Unfortunately, it's on a champ I rarely play.

Buying items like Rabadon Deathcap, give you a lot of survilability, function to take damage, if enemy has many AD champs. Very useful passive.
45 AP = 7 Armor.
100 AP = 15 Armor.
250 AP = 38 Armor.
400 AP = 60 Armor.
700 AP = 105 Armor.
1130 AP = 170 Armor.
If Veigar had this passive, all enemies will be killed, and Veigar will dont recieve damage from AD, like god tank.