Limited Set Guide

The Abzan are all about endurance, and nothing prepares you for a long game better than growing your creatures over time. You can activate an outlast ability during your main phase if the stack is empty—otherwise known as any time you could cast a sorcery. Outlast abilities include the tap symbol, so a creature's outlast ability can't be activated unless that creature has been under your control continuously since the start of the turn (unless it has haste). When an outlast ability resolves, put a +1/+1 counter on the creature.

Spells with delve are very powerful, but usually have a high mana cost. Fortunately, you don't need to pay all of it with mana. The Sultai's ruthlessness leads them to use every resource at their disposal, even the dead. As you're paying for the spell, you can exile cards from your graveyard. Each card you exile this way pays for one generic mana.

The Temur (the green-blue-red clan) signature mechanic is ferocious. Like raid, ferocious is an ability word. It has no rules meaning, but is used to highlight abilities that care about you controlling a creature with power 4 or greater.