Cheatsheet: Fate Reforged
Bolster is a keyword action; accompanying the keyword will be a number which tells you how many +1/+1 counters will be created from the action. When a spell or creature with Bolster resolves, the Bolster action is completed without using the stack. The creature receives the counters when you Bolster, not when you cast the spell/creature.
To clarify in the instance of the Bolster action on a creature: the Bolster trigger does use the stack, but once priority is passed on the action, the action is then completed without use of the stack (e.g., your opponent can kill a creature you control with the bolster ability on the stack, but cannot respond to the action of choosing the creature you control to bolster).
To Bolster, you choose the creature you control with the least toughness; in the event of a tie, you may choose one of those creatures. Bolster does not target a creature.
9 cards feature the bolster action (5 creatures, 2 instants and 2 sorceries):
The aplty named dash ability is an alternate casting cost option for the creature. When a creature is dashed, it gains haste and returns to its owner's hand at the beginning of the next end step. Dashing a creature is still casting it - it goes on the stack like a normally casted creature, and may be targeted on the stack the same way (e.g., with a counterspell).
In any event where the creature goes to the graveyard or is exiled from play, the return provision will not trigger. Similarly, if the creature leaves play and comes back into play (e.g., from an Astral Slide effect), the returned instance of the card will not return to hand, but rather will stay on the battlefield.
8 creatures feature the dash ability:
A manifested card is put onto the battlefield face down. While manifested (i.e., face down), it functions just like a morph - it is a 2/2 colorless creature without any characteristics whatsoever (no name, no abilities, no types). A manifested card may perform all actions other creatures can perform (attack, block, ability to be targeted as a creature, etc.).
Any time you have priority, you may turn a manifested creature card face up by revealing its mana cost and paying that mana cost. Similar to morphing a creature, the act of turning the card face up does not use the stack and cannot be responded to (any trigger upon turning it face up would use the stack as normal). A manifested creature card with the morph ability may be turned face up by paying either its morph cost or its casting cost. Non-creature cards that have been manifested may not be turned face up in this manner.
A manifested creature that is turned face up is not a new creature. State-based effects affecting that creature remain when turned over (any counters on it remain, auras/equipment attached remain, etc.). Enter the battlefield effects do not trigger.
In the event a card turns a manifested instant/sorcery card from face down face up, you reveal the card and it stays on the battlefield face down.
18 cards feature the Manifest mechanic (6 creatures, 4 enchantments, 6 sorceries and 2 instants):
As you pay the mana cost for a spell with Delve, you may exile cards from your graveyard. Each card exiled pays for 1 colorless mana; colored mana in the mana cost cannot be paid with Delve. You may not exile more cards than it takes to pay for all the colorless mana in the spell's cost.
Cards exiled with Delve are part of the casting cost of the card - as such, if the spell is countered, those cards remain exiled.
8 cards feature the Delve mechanic:
Ferocious is an "ability word" - when the spell resolves, you check your board state to determine if you have at least one creature with power 4 or greater; you have ferocious and the ability on the card resolves. Ferocious is a binary function - it either applies or it does not apply; having multiple 4+ power creatures does not matter.
Where Ferocious is an activated ability, the check for Ferocious happens upon activation. As a result, even if the creature providing Ferocious dies in response to your activation, the ability will still resolve.
8 cards feature the Ferocious mechanic:
Prowess is a triggered ability; it triggers when you play a noncreature spell, causing the creature with Prowess to get +1/+1 until end of turn. Creature spells will not trigger the ability, including any creatures that have other card types (like the gods from Theros block). Prowss triggers go on the top of the stack - on top of whateve spell has caused the ability to trigger, and thus making it resolve prior to the spell. Because it is a separate trigger generated from the casting of a spell, a counter on that spell will not affect the Prowess trigger.
8 creatures feature the Prowess mechanic: