3 possible setups: a) pure light sorc

pure cold sorc c) cold/fire hybrid sorc
pure fire sorc isn't working because most monsters are fire immune and can't be broken by infinity.
pure light sorc is strongest/fastest but needs infinity merc. pure cold is safest and also fast but can't farm areas with many cold immunes. hybrid sorc is cheap to build and can farm any area but is slower than the other two.