this is a trick question thread, expect the questions to be tricky
the answer is -499, since your opponent's hp pool caps at 500
I will answer both of your questions then
@XYTWO, since spells are different from permanents, you can have 6 catas, you can have 5 PUs in your hand, you nymph can have 499 hp, PU it, then launch, which would result in 65*5 damage, so.. 325
@DDevans, trainer, X100 quanta, your hand: 6 granite skins, 2 SoDs, so... 590