Tarkir: Dragonstorm (TDM)

Omen

The rule

A Dragon card has a second Omen half (a sorcery or an instant): you may cast either half; if you cast the Omen, the card is then shuffled into your library.

In play

Cast the Omen early, then maybe find the Dragon later: these cards are useful spells early in the game and Dragons later on.

The other mechanics of the set

The Omen cards, ranked

Ranked by win rate when the card is in hand (the cards with few games follow, by pick rating).