Extended Spell Shopping List:

Summon Butterflies (Blocks LoS with mutators) Apportation (Must have for Chei followers. Moving is for losers) Regeneration (You don't get much rest in Hell) Summon Lightning Spire (never unlearn this spell) Borngjors Vile Clutch (Very important all around) Summon Mana Viper (take down those pesky casters) Aura of Abjuration (Only allow Summons when you want them as Ignition fodder) Iron Shot (You want one good universal damage spell. LCS is also good but I like the extra range) Spellforged Servitor (Kills stuff for you as long as you make sure to forget all low level Conjurations) Controlled Blink (Must Have for endgame Chei) Death's Door (In case everything else fails) Ignition (Make Board go Boom)