PERMADEATH per mission - Once you die,You dont go back,there's no defibs or respawning.
Upon Someones death it activates an Dramatic-SlowMotion-Camera on the Person's position that died,It can be annoying.
So keep it in mind whlist one of your teammates gets isolated and is getting battered,watch the health to be somewhat prepared.

There isn't any "Regeneration Health over time" Mechanic,You must seek for the Medkits (Which are very rare) and the help of medic,The Medic equipment,Med packs and Med gun have limited usability.

Stuff Doesn't drop out of enemies,which means someone always has to get Ammo pack, resupply locations are predetermined.

The Loadouts are always the same.
2 places for Main stuff,Weapons,Ammo packs,Turrets,And one for secondary equipment which contains mostly one-off utility gadgets or passives.

Alien Parasite(MELEE/LEAP) They Don't Spawn Randomly
"Parasites" They launch themselfs at you,and deal GREAT periodic dmg by ♥♥♥♥♥♥♥ with your insides.
You can't get them out of your body in ordinary ways such as punching/shooting the person that is infected,dont panic
Only med kit and Medics stuff can heal you.
Their bodies are very small and green,they can hide in dark very well
They are Spawning only on missions like in Syntek labs,the canals. and the last mission the Speaker will tell you about their presence only in the Syntek labs.
Though they can spawn on some hardcore difficulties and moded servers rather randomly.
They are very vulnerable.


Swarm (MELEE) Yes thats the name. They spawn constantly from predetermined locations or by a trigger.
They are the Common enemy across all the missions,They are dealing a bunch of good dmg,but really they are quite weak,They are fast,dont try running from them,and or rolling.
They look like your standard necromporh-dog.
Go for the middle of their body for maximum effect.

Shieldbugs (MELEE)
They have a few defined locations you should expect them to show up.
There's about 2-4 of them on the end of the last mission.
They usually shield themselfs after taking dmg from their front,They can knock you down or throw you across the room. Their attack is rather fast,if you get pinned down try to dodge/roll.
Big-Medium body,Shield,Vulnerable back.. Try to bait an attack,the moment they're forced into their hitting animation they're much easier to attack from behind.

Mortars(RANGED/MORTAR)
They Don't Spawn Randomly.
They are quite common after Syntek labs,They Launch mortar "mines" the mines dont activate upon you touching it,they automatically explode after like 3 seconds while being on the ground.
Big body,Tanky,Their body can damage upon direct impact with yours,although very small dmg,it knocks you back.

Oh,and
Spitters (RANGED/PROJECTILE)
They spawn in many designated places. Usually near the defense objectives.
They are common across levels,They launch a few slow balls of acid at you,they can be dodged.
They are a bit tankier than the Swarmies,Their dmg is quite poor,but dont underestimate them. It throws your character off stance briefly, try to eliminate them the moment you can do so safely.

There are 4 classes and 2 characters each
There are weapons that only specific classes can use.

Officer/Sergeant (Made for Buffing Nearby Players and Killing)

Heavy Gunners (Made for Killing)

Medic (Heal and/or Support)

Technican (Required in "some" maps to fulfill certain objectives such as hacking doors/terminals etc, prepare for a minigame under stress)

Every Class can do pretty job at killing so it doesnt matter.But Heavy is Like Anti-Horde made class.

There are 8 Characters (2 per class)
Medics(My favourite)

Faith
Excellent Healer
Traits
5/5 Heal
3/3 Cure(vsParasites)
1/5 Weapon DMG Bonus
2/5 Faster Reload
3/5 SPEED
(Preffered for Advanced and Supportive Players)


Bastille
Combat Medic
Traits
4/5 Heal
1/3 Cure(vsParasites)
3/5 Weapon DMG Bonus
3/5 Faster Reload
3/5 Effectivness of Adrenaline.
(Preffered for Begineers BUT REMEMBER TO CHANGE TO FAITH IN INFESTATION STAGES THAT START FROM SYNTEK)

Technicans

Crash
Specialist
Traits
3/3 Scanner
1/3 Engineering
3/5 Weapon DMG Bonus
4/5 Faster Reload
2/5 Explosives DMG Bonus

Vegas
Genius and a Hard-hitter
Traits
3/3 Scanner
3/3 Engineering
3/5 +HP
2/5 Faster Reload
4/5 +MELEE DMG

Officers

Sarge
Excellent Buffer
Traits
5/5 DMG Buff Aura
2/5 Vindicator (Shotgun-like weapon) DMG
2/5 +Explosives DMG
4/5 +HP 3/5 +Weapon DMG

Jeager
Great Exterminator
Traits
3/5 +DMG Buff Aura
5/5 +Vindicator DMG
4/5 +Explosives DMG
3/5 +HP 2/5 MELEE DMG

Heavy Gunners

Wildcat
Fast and Furious
Traits
4/5 +Autogun DMG
2/5 +Chance of Piercing
4/5 +Weapon DMG
3/5 Faster Reload
4/5 +SPEED

Wolfe "A Tank"
Traits
5/5 +Autogun DMG
3/5 +Chance of Piercing
2/5 +Weapon DMG
2/5 Faster Reload
3/5 +HP

Expedition Placement 2/1/1

2 In Front
Mainly kills mid-front horde.
(You can't fail shooting straight into horde I think)

1 In Mid
Supports the front players and watches the Right and Left side.
(Survival is crucial for techs and medics therefore they should be in the middle of formation)

1 In Back
Mainly watching the backs,picking off stragglers but also quickly helping out other players if such need arrives.

• Try to Remember Spawn Mechanics.
  
  
• Campers aren't rewarded,you must push on or run out of ammo.
  
  
• Stay Together. Be spaced out(in case of a spitter) and cover your angles.
  
  
• Wait for the team,dont abandon your teammates (Unless you are master at this game ;d but that's pretty dickish).
  
  
• Dont Rush, take your time equal to your level but to be honest, the faster you get out is the most optimal as long as everyone knows what's happening.
  
  
• Watch your back, dark corners especially since usually the vents are hidden in them.
  
  
• If you run out of ammo or you're reloading, don't asume you can't do nothing about that last surviving alien that just happened to slip by, punch them, atleast it'll stagger their attack.
  
  
• Don't waste ammo,it's really hard to go by on some of these levels if you didn't already get ammo packs with you.
  
  
• Use Right Mouse Button to punch some isolated aliens (max 1-3) and save some ammo.<Don't try on higher levels than Normal
  
  
• Don't use the chainsaw unless your team agrees.
  
  
• Team damage... dont make me explain it... No one likes it and you shouldn't either.

引用自 DragonFace(Author)：

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