Are you ready to be Embalmed?
The new set Amonkhet comes with some fun mechanics. Of note are Embalm, Aftermath and Exert:
Embalm:
Embalm is an activated ability you can activate if the creature card with embalm is in your graveyard. Notably you're not casting the card from the graveyard, so things that counter spells won't work against the embalm ability. The original creature spell can be countered, of course, but that just puts the card in the graveyard. I think you see where this is headed.
To activate an embalm ability, simply pay the embalm cost and exile the card. You do this any time you could cast a sorcery
Aftermath:
Aftermath lets you play a split card from your graveyard. It can be played in the same turn or let your opponent sweat it out for a bit and play it later.
Exert:
Exert lets you get a little more oomph out of your creatures for an added bonus, but a penalty later.
You make the decision whether to exert a creature as you declare it as an attacker. If you choose to have it exert, an ability will trigger and grant you some bonus. As a trade-off, the creature won't untap during your next turn. It's tired. Needs a nap. Attack more later.
You don't have to exert the creature as it attacks. If you don't, no ability will trigger, and it will untap normal during your next turn.
Brush up on all the mechanics before any release tournaments so you are ready to take advantage of these.