Accuracy X/-X: A cumulative, static ability that means, "Add X to each of this unit’s attack dice." and "Subtract X from each of this unit’s attack dice." respectively. Accuracy can’t alter "natural" rolls to affect Critical Hit, Fury, or Parry, but it can affect your chance against Armor. If a unit gets the Accuracy ability after you roll attack dice, it's too late to affect the hits.
Alternative Cost
Alternative Cost: [cost]: A selective, static effect that means, "Instead of paying the build cost of this card, you may complete this card by paying the [cost] listed." Alternative Cost must be paid in full, if it is not possible to pay the [cost] completely, you can't complete the card. You must pay the [cost] in the order listed. Any ability that reduces the normal cost to complete a card does not reduce the [cost] in that card's Alternative Cost, unless the ability specifically says so.
Ambush
Ambush X: A layered, activated ability that means, "If your opponent deploys, moves, or puts a unit into this arena, this unit does X dice of damage to that unit." Each Ambush can be used once per instance of a unit being deployed, moved, or put.
Armor
Armor: An isolated, static ability that means, "This unit can only be hit on a roll of 5 or more." Armor works against dice of damage and attack dice. It redefines what die roll is required to hit a unit. It doesn’t modify the die roll like Accuracy. A unit with Accuracy 1 attacking a unit with Armor hits with 4's, 5's, and 6's.
Avenge
Avenge X: A cumulative, triggered ability that means, "Whenever damage from an attacking unit causes one of your other units in the same arena as this unit to be discarded, this unit does X dice of damage to the attacking unit when the attack ends."
Bounty
Bounty: [bonus]: A layered ability triggered during a unit discard that means, "When another unit is discarded by damage from this unit, you gain the following when your next build step starts." Bounty triggers even if the attacking unit leaves play. Bounty works in the build zone. You will gain the bounty even if the attacking unit is sent to the discard pile. The unit can't collect a bounty on itself.
Critical Hit
Critical Hit X: A cumulative ability triggered during the pending damage POP that means, "If you rolled at least one natural six with this unit's attack dice, this unit does X more damage for this attack." Only one natural "6" counts in the attack roll after re-rolls. If a unit gets the Critical Hit ability after you roll attack dice, it's too late to affect the damage. Accuracy can't increase the die roll to a natural "6". However, you or your opponent may use an effect to re-roll dice to affect the number of natural sixes. (You only count the six, if any, from the roll used for the attack.) Critical Hit applies only to dice rolled for an attack, not to dice rolls for abilities like Retaliate.
Deflect
Deflect X: A layered ability activated during the damage prevention POP that means, "Prevent X damage to this unit, and this unit may do that much damage to a unit of your choice in the same arena." Deflect creates new damage that can be done to any unit in the arena (even itself). Deflect may be deflected any number of times. Damage is applied after all prevention and deflects resolve. The damage that the unit does equals the damage it prevented. You can play each Deflect effect only once for each source of damage. Deflect as much damage as you can up to the Deflect value.
Double Damage
Double Damage: An isolated, static ability played during the damage placement POP that means, "Put 1 additional damage counter on the defending unit for each 1 damage that wasn't prevented." Damage counters placed by a unit with Double Damage are in addition to the counters that would be placed normally if the attacking unit did not have Double Damage.
Double Strike
Double Strike: An isolated, static ability played after the attack end POP that means, "You may choose a unit that this unit can attack. This unit attacks that unit. Play only if this unit just attacked and only if it tapped for that attack." The unit must tap for the first attack, not the second. If it untaps, it may double strike again. Double Strike doesn't allow you to attack your own units.
Equip
Equip: A selective effect on Equipment activated during the build step that means, "Attach this Equipment to a unit. Play only during your build step." You can pay the Equip cost only once per turn.
Evade
Evade X: A layered ability activated during the damage prevention POP that means, "Prevent up to X damage to this unit." You can play Evade only once for each instance of damage. You don't have to use all of the Evade. You choose how much damage to Evade up to X, even if the full amount of damage or more is pending.
Focus
Focus X: A cumulative ability triggered by the initial dice roll that means, "When you roll at least one natural five with this unit's attack dice before re-roll, this unit gets +X power for its next attack." Only the first natural "5" counts. A five rolled after re-roll doesn't matter. Focus applies only to dice rolled for an attack, not to dice rolls for abilities like Retaliate. Accuracy can't increase the die roll to a natural "5."
Fury
Fury X: A cumulative ability triggered by the initial dice roll that means, "When you roll at least one natural four with this unit's attack dice before re-roll, roll X additional attack dice." Only the first natural "4" counts. A four rolled after re-roll doesn't matter. If your unit gets the Fury ability after you roll attack dice, it's too late to roll additional attack dice. Fury applies only to dice rolled for an attack, not to dice rolls for abilities like Retaliate. Accuracy can't increase the die roll to a natural "4."
Hidden Cost
Hidden Cost X: A selective, static effect that means, "As long as you have a number of build counters on this card equal to X or the unit's current build cost (whichever is less), you may complete it anytime by paying Force for the remaining build cost, if any." Effects and stacking rules may reduce the build cost. You do not need to pay Force if the build cost is within the Hidden Cost integer. You can deploy it to the build zone. Hidden cost can only be played if the card is partially built and has the required number of build counters on it. You may use Hidden cost anytime, even during any Play-or-Pass chances not reserved for re-roll, damage prevention, or disrupt POP chances. If there are a number of build counters on the unit equal to or greater than the Hidden Cost integer, you do not need to pay any Force. You may not use Hidden Cost to deploy a Pilot to a unit.
Inspiration
Inspiration: An isolated, static ability that means, "Each of your other units in this arena gets +10 speed, +1 power, and +1 health."
Parry
Parry X: A cumulative ability triggered during the damage prevention POP that means, "If the attacking unit rolled at least one natural '1' against this unit, prevent X damage to this unit." Only one natural "1" is counted from the attack roll after re-rolls. Parry doesn't prevent damage from a parrying unit unless it attacks itself. Parry can't affect unpreventable damage. If a unit gets the Parry ability after you roll attack dice, it's too late to affect the damage. Accuracy can't decrease the die roll to a natural "1". However, you or your opponent may use an effect to re-roll dice to affect the number of natural ones. (You only count the 1, if any, from the roll used for the attack.) Parry applies only to dice rolled for an attack, not to dice rolls for abilities like Retaliate.
Precision
Precision: An isolated, static ability that means, "This unit cannot be intercepted." An attacking unit with Precision cannot have the target of its attack changed by a unit with the Intercept ability. "Elude" is the former name of this keyword. Treat any unit with Elude as if it has Precision instead.
Protect
Protect X: A layered ability activated during the damage prevention POP that means, "Prevent up to X damage to one of your other units in this arena." You can play Protect only once for each instance of damage. You don't have to use all of the Protect. You choose how much damage to Protect up to X, even if the full amount of damage or more is pending.
Retaliate
Retaliate X: A layered ability activated during the attack POP that means, "If a unit in the same arena as this unit is attacking this unit, this unit does X dice of damage to that unit when the attack ends." A Retaliate ability without an activation cost has a printed cost of "Pay 0 Force -->". Retaliate resolves when the attack ends, even if your unit gets discarded. Retaliate dice are just dice of damage, not attack dice, and can trigger Stun. Retaliate based on a unit’s power is based on its total power at the time the Retaliate is activated. Retaliate doesn't work with attacks from another arena (such as Bombard and Ion Cannon) or the build zone. A unit may retaliate against itself if it attacks itself. Each Retaliate may be used once per attack. Each defending unit can activate Retaliate during the attack POP, which resolve in their order when the attack ends, even if the retaliating unit is discarded.
Stack
Stack: [List]: A layered, static ability that means "You may put a listed card under this unit as part of its stack." The listed cards can't be on top of the stack. Cards with the Stack ability don't count as the cards listed and don't contest with any of the listed cards. If a card is listed by its name you can't stack a card with a different name unless it satisfies a different criteria in the [list] or they represent the same unit. (See the "Different Versions with Different Names" section in the rules PDF) Unlike a normal stack, you can only have one version of each unique unit from the [list] in the stack. Non-unique cards listed on a card with the Stack ability are permitted to form a part of the stack and you can have multiple cards with the same name in the stack as long as they are non-unique. Cards added to a card's stack using the Stack ability cannot exceed the 4 card maximum normal stacking rule. If a unique card with the Stack ability has another version of itself move to the top of it's stack, discard any cards in the stack that can't stack with the new version on top of the stack.
Switch
Switch: [1st/2nd/3rd type effect]: A layered, static ability that means, "As long as this unit is in the first arena listed on its type line, it gets the effects listed to the left of the first slash. As long as this unit is in the second arena listed on its type line, it gets the effects listed to the right of the first slash. As long as this unit is in the third arena listed on its type line, if any, it gets the effects listed to the right of the second slash, if any." If it says "None" as one of the arena type's effect, it means that it gets no extra effects while in that arena. The unit's Switch effects will correspond to the types listed on the unit's type line. There won't be a slash for an arena not listed in the unit's type. Switch doesn't allow units to change arenas during the battle phase.