Perk synergies

Perk synergies are powerful bonuses that activate when their three associated level perks are acquired.

If your build already includes 2 out of 3 perks required to unlock a synergy bonus, it is always worth considering if getting the third, perhaps unappealing on its own, perk, and thus activating the synergy, wouldn't increase the build's power level more than picking a good perk that doesn't contribute to any synergy.

Name	Perks	Bonus
Adaptive Barrier	Reinforced Endurance + Vital Shielding + Energy Deflection	If your damage resistance (DR) is higher than your attacker's, you gain a damage multiplier equal to the difference between your DR and theirs. If your attacker's DR is higher than yours, you reduce their damage multiplier by the difference instead.
Architect	Turret Mechanic + Animal Friend + Engineer	Reduces turret building cooldown to 60 seconds and upgrades the weapon to a heavy double minigun. Explosive barrels are built 10 hexes ahead of the player, and the build cost is reduced to one advanced gunpowder and one good metal part. Sandbags are built three at a time, covering the player's frontside hexes. Land mines always cripple legs.
Armor King	Dodger + Quick Recovery + Livewire	-25 to attackers' AC mod +5% Damage Protection +10 DT cap -15% character size
Bonus HtH Rapid	Gain Strength + In Your Face! + Better HtH Criticals	+5 Strength for Heavy Handed calculations +100 AP Regen when using a melee weapon
Bonus HtH Speed	Bonus HtH Damage + Bonus HtH Attacks + Vampire	+10% Movement Speed +0.3% Movement Speed for every 1% of character size above 100% -10% Attack Delay
Burster	Bonus Ranged Damage + More Ranged Damage + Death Sense	+75% chance to deal +100% damage when attacking a target on an adjacent hex (a.k.a. "1-hexing")
Deadly Momentum	Focused Strike + Deadeye + Bonus Damage Multi	When Focused Strike is fully charged (50/50 stacks), your damage is doubled
Iron Man	Iron Limbs + Man of Steel + Unbreakable	+30% Critical Chance Resistance and Critical Roll Resistance -20% critical damage received
Lethal Death	Living Anatomy + Weapon Handling + Gunner	+25% more lethal damage when the target is below 50% HP +10% Lethality (hitting targets with max HP % below your Lethality % adds 2137 damage to your attack)
Marksman	Better Criticals + Spray and Pray + Hit the Gaps	+3% additional critical chance for aimed attacks per point of Luck (this stacks with the regular +4% bonus for a total of +7%) 150% Critical Power when the target is less than 30 hexes away
Medicine Doctor	Healer + Medic + Surgeon	Healing others also heals you for 50% of the amount +20% DT penetration protection when below 50% HP +30% DR penetration protection when below 50% HP
Mysterious Stranger	Party Member + Gain Charisma + Cult of Personality	All NPC companions gain 30% increased Damage Protection Whenever you enter a new location, an NPC companion spawns: their gear tier matches yours; their build is randomized; their power level scales with the current patch number Whenever you re-enter the battlefield during War Events, two NPC soldiers spawn to fight alongside you; the effect has a 30-second cooldown
Nader	Heave Ho! + Hit and Run + Demolition Boy	Grenades gain weapon perks based on your armor perks, see Weapons#Grenade perks for details. +1 AP drained from your targets per hit
Ninja	Gain Perception + Ghost + Silent Running	+20 Stealth +20 Stealth when next to a wall (stacks with the unconditional +20 for a total of +40). -50% AP cost of activating sneak
Pyro!	Pyromaniac + Firefighter + Bonus Battle Stats	50% of Pyromaniac's and Phoenix Module's fire damage bonus gained as extra lethal damage -10% to your targets' lethal damage defenses +40% character size
Quartermaster	Earlier Sequence + Quick Pockets + Bonus AP Regen	All tools function directly from inventory Tool efficiency increased by 100% Can use two medications at once Carry weight is doubled Motion sensors and armor require only 1 MFC to fully charge The cost of discharging armor is halved Swapping armor does not consume action points
Quick Fingers	Bonus Rate of Fire + Fast Attacks + Cowboy	-50% attack delay for single shots (excluding melee and throwing) +17% damage multiplier against targets larger than you
Ranger	Right Between the Eyes + Sharpshooter + Awareness	+5 range for throwing and ranged weapons +50% Critical Chance Resistance penetration when the target is 60+ hexes away +50% Critical Power Resistance penetration when the target is 60+ hexes away
Slayer	More Critical + Even More Criticals + Gain Luck	+40 to critical roll. -80% to target's armor's critical roll protection.
Speedboy	Action Boy + Bonus Move + Gain Agility	+25% Bonus AP. +10% to Movement Speed bonus caps -50% attack delay from using items that restore hit points -50% reload cost
Stealth Master	Undetected + Phantom Presence + Gain Intelligence	Standing still for 5s while in sneak mode without combat timer lets you become completely invisible Activating Sneak reduces combat timer to 5s Whenever your HP drops below 0, you enter sneak mode automatically
Tank	Adrenaline Rush + Toughness + Lethal Protection	+10 to all defensive rolls -30% to attackers' melee damage Minimum damage multiplier capped at 80% +10% to damage multiplier against targets below your character size
Technician	Gain Implants + Synthetic + Cybernetic Eye	You can pick an additional level perk that can be changed at any time using the ~technician, or ~tech for short, command. Note that picking a perk you already have will have no effect.
Undying	Lone Wanderer + Providence + Stonewall	When you die, you are automatically revived with 50% HP and given 5 seconds of damage immunity. Cooldown: 180 seconds.
Vanishing Act	Baiter + Crasher + Long Arms	When hit by a player, you gain +500 Stealth for 1 second and automatically enter Sneak mode (Cooldown: 3 seconds).
Vigor Boost	Atomic Savant + Muscular Physique + Coolheaded	Whenever you take damage, you have a chance to gain 1 second of immunity based on your HP % after the hit. Your remaining hit points >90% 76–90% 51–75% 26–50% 11–25% 1–10% <1% Chance to gain immunity 0% 10% 15% 20% 30% 40% 50%
Vitality	Gain Endurance + Faster Healing + Lifegiver	+50% Healing Rate. Reduced the effect of Poison on Healing Rate from 50% to 25%. Reduced the effect of Bleed on Healing Rate from 100% to 50%.