By the way, since it is possible to get any spell, I'm wondering if Calm Rage would push you over with just Poison Skull. I have not tried this strategy, but if someone gets Calm Rage from the Ore Cart maybe they could try it out and let us know if it will work since they'll be able to convert that early Rage into Mana for more Poison Skull casts.
Hmmm...
/C\/C\
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