Thunder Tower (aka EMD Lab) is a Zombie Mode map sets inside a mechanical production plans.


  • Thunder Tower (Most versions).
  • EMD Lab (West & Español).
  • Gravitron (Brazil).
  • ThunderStroke Tower (Vietnam).
  • ThunderStorm (Indonesia).
  • Jet Tower (Russia)


The agents fixed their gazes on the blue lights and followed them into the depths of a place they could not even begin to fathom. The foreground looked like a giant test tube in the abyss, with an endless set of stairs spiraling down the ground level. The ground level looked like a river of lightning, with a pillar of light from the center shooting off to an unknown place with a low hum. This sight was not meant for mortals.


It's a huge tube filled with mechanical machines ready to be destroyed within a disposal waste at the ground level. These robots are traveling downward in a long spiral ramp. They cause few sparks along the way, this is why the whole ramp is divided in two with an electrical force field powered by electrical rods.

These rods mainly serve as indicator to detect which floor the mechs are at. If blue, they reached F1, if red they reached B1. For each mechs that goes to waste, the rods electrocute the whole area (-10 HP). Which means a normal row of mechs would kill every players. Also the mechs shock players too close from them (-2 HP).

The whole tube is low on gravity (similar to Orbital Station), easing the movement for anyone in the facility. If anything, the place provide some jump pad to get on top faster. There are many short tunnels, these are all zombies spawns, but some of them appear from emergency doors on top.

The ground level is a huge industrial fans seems to be served for anti-gravity experiments. Below it, sits the guardian of the place, deep into toxic liquid. Getting too close of the bottom will intoxicate players (-5 HP). When the boss emerge, it destroys the fan in a cutscene, however the anti-gravity device is still functional.


The main goal on this map is to score a high amount of points by combining multiple mechs together. Once three or more of the same type are linked together, they will explode and give additional points to every player. Any types give the same amount, which is 300 points multiply by total mechs destroyed. What matters is how many there is in the connection and how many players in room.

There's always only one row of mechs at a time, once they are all destroyed, another row will appear. If there's a gap in a group and two mechs of the same type are linked, the group in front with all its mechs attached to it will be forced to backtrack to meet their pairs. Most have certain attribution and will act differently when exploding.

  • DMD: Will simply explode with his pairs, they are default mechinical machines. = [White Robots]
  • Destructor: Will destroy one mech ahead and behind the pairs and can screw up most combos. = [Grey Robots]
  • Blockers: Will stop the mechs behind until they explodes, which is useful in ground levels. = [Yellow Robots]
  • Fans: Will push the mechs behind to the floor's starting point then explodes (also useful in ground levels). = [Blue Robots]
  • TNTs: Will destroy eight mechs on each sides, to be avoided or else you'll miss potential combos. = [Red Robots]

Tips & Strategy

  • If you are newbie, let the whole row appear first before deciding which one to shoot. Bigger combo may still be hidden behind the wall and by shooting fast, you may miss them
  • Always target Fans and Blockers first if they are at the start of the row. This gives you more time to score combo
  • Sometimes destroy and match the Blockers when the whole row has appeared so you will have a little more time to decide on which mechs to destroy.
  • Start with DMD first, then Destructors, as they can destroy some other mechs and cause smaller combo to break
  • TNTs should be taken care of individually ASAP, especially when playing in public. Newbie players may be tempted to match them first, thus destroying the whole row
  • If possible, start matching combo from left to right. That way the mechs won't be pulled back and cause unnecessary combo that may screw up other combos available
  • If you know that a Destructors Combo will end the row by destroying other Mechs near them and you can't match any more combo, destroy those Mechs first before matching the Destructors.
  • Note that Destructors will only destroy one mech right next to him - if there is a gap, then the other mech will be unaffected. Use this to your advantage and create gaps whenever possible so you can score more combo. An example is in Round 18: Instead of matching 11 Destructors right away, destroy one next to the DMDs on the Right. This way, when you match the remaining 10 Destructors, the two DMDs on the right side will surivive and match up with one DMD at the end of the row, forming another combo.
  • Sometimes you must choose carefully between combo 3 or 4. Make sure that you get the most possible points out of them instead of just the number in the combo. A nice example is in Round 1: You can match 2 combo 4, but it's best to match 3 combo 3 which gives out more points (2700 vs 2400).
  • Destructors are capable of cutting a line short if it explodes INSIDE the tower base - for example, when 3 Destructors are the last one from B2 base and a long row of B1 is coming up, it's possible to skip the entire B1 row by matching them while one or two are hidden behind B1 wall. This method is useful to save time when players have VVIPs and everyone already reached target points for Crystal crates.
  • To get a Crystal Crates for the remaining players. It is best to let 1 person do the combo's while the others shoot the zombies. it doesn't matter if nobody has a VIP account aslong as the person doing the combo's gets most of the combo points. 550000 is needed befor the last boss is destroyed to get a crystal crate.


  • Zombies: Common zombies from previous maps but re-textured again, these includes: Mutants (Steel Jaw), Dreads (Hell Claws), Gorillas (Steel Beast), Crawlers (Metal Assassins) and Jumpers.
  • Mechs: They are on their way to be disposed of, these includes: DMD, Destructor, TNTs, Blockers and Fans.
  • Bosses: Giant Predator & Predator Core. Mysterious Girl is also back with her two twins sisters.


  • Wave 8: Anti-Gravity will activate and a total of 100 mechs will spawn over time in two rows, as soldiers make combos.
  • Wave 16: A similar bonus to Dinner Theater's where an army of jumpers fall down from the top. Each jumpers requires one bullet to kill. Purple ones give out 500 points (100 points in CF ID)and yellow ones fill the boost bar; even if the bonus time runs out. In order to make the bonus easier, the bullet times will also assists two times.
  • Wave 18: An important combo not to miss, consisting of eleven mechs, thus giving 3300 points.
  • Wave 20: A huge amount of Assassin drops down from the emergency door on the top, making them a big threat due to their large numbers. It's best to camp on both side of the ramp to 4th floor and kill them all before they start moving (Using FAL Camo is recommended)
  • Wave 24: Three Mysterious Girls will appear (same color bonuses, but Purple one now gives 10000 points) and will start running all over the map.
  • Wave 27: Many Gorillas appeared at Floor 1st, plus an extremely long mechs line appear in Floor 2nd. It's best to have 2 players to score combo while the other two use FAL Camo to clear out the Gorillas. Don't let the mechs reach 1st Floor or the FAL Camo grenade may disrupt it
  • Wave 30: The boss will emerge in a cutscene. Upon his defeat, the core will appear and Anti-Grav will also activate to reach the core which would had most likely reach the top.
  • Wave 31: Another cutscene shows up after Giant Predator and its core have been defeated. Geared Serpent will emerge and soldiers must defeat him within 10 minutes to win his boss token.


  • Anti-Gravity: Activate at Wave 8 and 30, they allow players to freely move are the facility.
  • Bullet Time: Available in Wave 16 and 24, same concept as in Dinner Theater, it slows down movement.
  • Supply Crates: Like in most maps, crate will spawns every five waves to deliver grenades and hypomeds (Wave 15) and now Instant Heals (30 HP) gold crates. They fall from the top and will disappear at the bottom.
  • Ammo Carriers: Few crawlers will have ammo icon above their heads, killing them results in an instant refill.
  • Berserk: Replaced with a FAL Custom-Camo with enough ammo / grenades for the whole boost.


Main article: Giant Predator

Giant Predator is the final boss on any difficulty in this map, however in Normal difficulty, once defeated, his core will then start to harm soldiers with similar attacks. On his first form, the mechanical spider attempts to climb all the way up causing soldiers to be unable to get above him. His legs can also crush soldiers (-50 HP).

Whenever somebody is below, it will use a special tracking laser dangerous for anyone being chased by it. This is why it is best to always stay on top and shooting his leg to prevent him from climbing. Destroying the huge metal object on the ceiling to crush him, thus forcing him to fall few floors (you need the achievement Spider Hunter first).

The second form has more HPs but is as easy as his spider form. Doing the same attacks except he won't do the dangerous laser attack the spider can do. As soldiers can easily move with the anti-gravity, it is easier to dodge most of his lasers. Overall these bosses are far from being a threat.

To make the fight easier, supply crates will also drop during this battle, each wave consists of four Golden Health boxes (Instant heal 30 HP). If you run low on health, make sure to grab one of these, they will help greatly.

Hard Difficulty

Main article: Geared Serpent

Being the third map to feature Hard difficulty, EMD Lab also features one of the hardest bosses up to date, even harder than Blaze. Geared Serpent has a couple of instant-kill attacks which will cost soldiers plenty of time to recover, as well as his constant movement along the tower, making him harder to attack. Good tactics and powerful weapons are a must to beat this boss with minimum casualties as well as under 3 minutes mark for additional tokens.


This map use a new kind of reward, introducing a safe system. Whenever somebody finish a match, early leave or gets kicked, if they had enough points, just like any previous map, they would receive a prize. This time however, players receive a safe that can open any crates of the same color or any crates below.

This map also has its own crates, which can only be chosen from the safes. A player may choose between a normal crate or an EMD crates when opening a crate. A crystal offers every crates of their choice to be opened.

The EMD crystal come with a large variety of items, including: Boxing Gloves, ARX-160, G11 Blue Skull, M1216 Blue Skull, etc. The boss crate contains these items, plus a Predator Backpack, Mysterious Girl Doll, various namecards and sprays as well. It is probably one of the best and easiest reward crates to obtain.


  • This is the first time in CrossFire where a cutscene is used.
  • This map is the easiest one for everyone to obtain Crystal Safe, as long as they cooperate and do the combo properly.
  • The combo playstyle works similiar like Zuma Deluxe and other popular mini-puzzle games.
    • In CF China, the introduction of the map shows that Thunder Tower has given a code name as "Zuma".
  • On the middle of the 1F floor there is a special point, on which you can stand. When you stand on it all mutants became hunting you, but because you are unreachable, they are just standing alone. It can cause a bug ob 16-th level: hunters will be standing upstairs and will not jump out.
  • When playing this map in easy mode, the object above the map is indestructable even in round 20 and you have the achievement.


  • After December 2013 Christmas Patch in CF Indonesia, anti-gravity in round 30 is glitched and become non-functional - notification gets stuck "Anti-gravity will be enabled in 1 second". All animations (excluding cutscene) in round 8 and round 30 are disabled. Has been fixed on Soccer Mode Patch.
    • Sarcastically, this glitch happens in CFVN when players join in round 31 (hard difficulty), it prevents players to kill Geared Serpent in an easy way.
  • As of August patch in CF Vietnam, a glitch occurs that render the top objective indestructible, meaning no one can shoot to destroy it even if they have the Achievement.
  • Recent patches in CF Vietnam caused the supply drops to fall too fast, making it very hard to grab a health pack or TH-Grenade.
  • At CF Philippines, after the Thunder Tower hardmode has been implemented, the supplies fall way too fast that anyone can't get it, unless they jump way early before the supply has appeared.



Cross Fire China Thunder Tower's Hard Difficulty (Challenge Mode) GamePlay !

Cross Fire China Thunder Tower's Hard Difficulty (Challenge Mode) GamePlay !

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