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.
Area Damage
Area Damage X: A cumulative, triggered ability that means, "Whenever damage from this unit's attack causes a unit in this arena to be discarded, this unit may do X dice of damage to another unit in this arena."
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.
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.
Damage Control
Damage Control X: A cumulative, triggered ability that means, "When your build step starts, you may remove up to X damage counters from this unit."
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.
Enhance
Enhance: [Effect]: A selective, static effect that means, "You may play the following effect by paying the additional cost." The effect states whether you play it "instead" or "also". You must declare it to get its effect.
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.
Ferocity
Ferocity: An isolated, static ability that means, "Damage from this unit can't be prevented." Damage that can't prevented includes all damage coming from the unit with Ferocity, including damage from attacks, Ambush, Deflect, Retaliate, and other abilities. Units with Fortitude override this ability, and can prevent damage to themselves from units with Ferocity.
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.
Intercept
Intercept: A selective ability activated during the attack POP that means, "If one of your other units is being attacked in the same arena, the attacking unit now attacks this unit instead." Intercept doesn't end the attack. Any number of units may intercept an attack once for each instance of the effect. Each intercepting unit has been attacked. Intercept isn’t a prevention ability. Intercept doesn’t cause a new attack. (It is the same attack.) Your unit may intercept an attack from one of your own units (but not from itself) as long as that unit can attack it. If it can't attack the intercepting unit, you can pay its activation, but the defending unit won’t change. "For this attack" effects do not trigger for each intercept. Some effects may end because they don't apply to the new defending unit unless the effect's conditions are met by the new defending unit. An effect that addresses the attack can't be played for each intercept, but could continue.
Overkill
Overkill: An isolated ability triggered during the pending damage POP that means, "When this unit attacks, you may divide hits in excess of the defending unit's remaining health between that unit and another unit in the same arena." The player who controls the attacking unit decides how many hits (if any) in excess of the defending unit's remaining health to reassign as damage to the second unit. (That player can't change their mind afterward.) A number of hits equal to the defending unit's health must be assigned to the defending unit, and the remainder may be assigned to the defending unit or another unit in the same arena. Overkill damage is caused by the ability, not the die roll. Shields, Parry, and Armor have no effect against it, but damage prevention not specifying dice works normally. Both units resolve damage in tandem.
Pilot
[sub-type] Pilot: A layered, static ability written as "[sub-type] Pilot. The [sub-type] gets:… ." that means, "You may move this card onto or off of a non-Droid Space or Ground unit of the correct sub-type once during the build step. Ignore all other text on this card except its name, sub-type and health. The piloted unit can't have more than one Pilot." Treat all of a unit's Pilot abilities for a sub-type as a single Pilot ability for that sub-type. It grants abilities to that unit alone. See the "Pilots" section of the rules PDF for more info.
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.
Reduced Cost
Reduced Cost X: A selective, static effect that means, "This card’s cost is X if the listed condition is met." Reduced Cost on cards refers to the build cost, except for Battle cards, where it refers to the Force activation cost. For this keyword, the conditional statement will always start with "If" for clarity. The condition must be met in order for you to be able to pay the "Reduced Cost."
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.
Shields
Shields X: A cumulative, static ability that means, "The attacking unit gets –X power against this unit." Shields only matters when attack dice are rolled. If you give a unit Shields after your opponent has rolled for damage, it doesn't affect the roll.
Stealth
Stealth: An isolated, static ability that means, "This unit can't be attacked unless it's tapped or has damage counters on it." An untapped and undamaged unit with Stealth can still be affected by alternative types of damage. (Such as Overkill.) As long as the unit has any number of damage counters on it, it can't use Stealth.
Stun
Stun X: A cumulative ability triggered during the damage placement POP that means, "When this unit damages another unit, that unit gets –X power until end of battle." If no damage counters are placed as a result of damage, Stun doesn't occur. Stun works anytime the unit damages another unit, not just when it attacks. Only the unit with both Deflect and Stun abilities can stun when it activates its Deflect.
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.
Redirect
Redirect: An activated ability that means, "If this unit is attacked, choose one of your other units that can be attacked and damaged in this arena. The attacking unit attacks the chosen unit instead." Precision will cut through Redirect just as it cuts through Intercept. However, there are cards that can cause a unit to lose Precision, or part of its game text.