Go for the Throat > Doom Blade

Single-target discard generally forces you to trade card advantage against two opponents for card advantage against a single opponent, and you will quite often force them to get rid of the worst card in their hand instead of the real threats. You will want to focus on asymmetrical effects that let you slowly grind hands down, like Pain Magnification. If you're willing to, you can dabble in filling your own grave for later with cards like Windfall and Burning Inquiry so that your discard spells do more beyond their immediate impact, as well as giving you the opportunity to pull a KO out of nowhere.

I see you got many creatures that need to deal combat damage to a player, I would add Lightning Greaves and/or Swiftfoot Boots for surprise factor and extra protection. Also few more boardwipes, in case your opponents get one of those :)