Prioritize Rod of Ages, Archangel's Staff, and Malignance for scaling and mana, considering Conqueror or Electrocute runes.
Kassadin becomes powerful at level 16 but demands significant team resources and might not carry as dominantly as in the past.
Malignance, Archangel's, and max ultimate provide a 1-second Riftwalk cooldown at 16 with virtually unlimited mana.
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