Disdainful Stroke

Counter target spell with converted mana cost 4 or greater.

Sleep

Chart a Course

1U

Dive Down

U

Siren Stormtamer

U

Syncopate

Counter target spell unless its controller pays {X}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Curious Obsession

Enchant creature Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, you may draw a card." At the beginning of your end step, if you didn't attack with a creature this turn, sacrifice Curious Obsession.

Mist-Cloaked Herald

Mist-Cloaked Herald can't be blocked.

Negate

Counter target noncreature spell.

Opt

Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) Draw a card.

Essence Scatter

Counter target creature spell.