Gun Towers...
	Kills...
	Laser Position...
	Resources...
	Upgrading Towers...
	Various Achievements...

The gun tower provides an adequate offense at an affordable price. It is the most basic structure in the game and fires relatively weak ammunition at a very high clip within a tight radius. However their down side is that they can only be committed to one enemy at a time and they do no area damage.

Your score is based on your kills and you get a score for each kill which is influenced by the following factors.

1) How many unspent resources you currently have.
2) How many cores in your housing.
3) Whether or not the kill occurs within the area of a score boost tower.
4) Whether or not the kill occurs within the special resource weapon area of effect.
5) The value of the alien (not all are the same).

Make sure that if you plan on using lasers that you spread them out so that they become as effective as possible.

Resources influence your score the most so it is important that you try to build your resources up early in the game where they compound much better than late resources. Resources accumulate with:

1. Time. Every 'tick' you get ten more resources.
2. Waves. Every few waves you will get a decent bonus of resources.
3. When you employ the resource special weapon, you will get an increase in resources.

Once you have accumulated enough credits from destroying your enemy you will be able to upgrade your towers to their second and third forms which will provide increased damage and range with each iteration. What you are aiming for is maximising your damage output over as long a path as possible over the longest amount of clock-time possible.

Complete the following achievements to collect their Xbox Live Gamerscore points.

Achievement	How to unlock
10 Items No less (10 points)	Enable a Tower Augmentation Item on 10 Towers.
Alien Tears (10 points)	Earn a gold medal on every mission in Story mode.
Annihilator (10 points)	Kill 10,000 aliens.
Arsenal (10 points)	Build 20 towers of any type in one mission.
Base Defender (100 points)	Complete the single player campaign in Story Mode.
Boot Camp (10 points)	Finish all the missions in Chapter 1 in Story Mode.
Brothers In Arms (10 points)	Earn a Bronze (or better) medal in a Coordinated Defense Multiplayer mission.
Burn Baby Burn (10 points)	Build 100 Inferno towers.
Close Call (10 points)	Save a core that is less than 10 seconds away from the map's exit point.
Confident (10 points)	Use the speed up control at 3x for a total of 60 seconds in any mission.
Death From Above (10 points)	Use the Orbital Laser Special Weapon (General Cai).
Diversity (10 points)	Build at least 1 of each tower type in any single mission.
Eradicator (10 points)	Kill 100 aliens.
Exterminator (10 points)	Kill 1000 aliens.
Field Promotion (10 points)	Earn a silver (or better) medal.
Filthy Rich (30 points)	Win a mission with at least 10,000 resources remaining.
Firebug (10 points)	Using only Inferno towers, Win any Chapter 4 (or later) mission.
First Blood (10 points)	Kill 1 alien.
Flawless Victory (10 points)	Earn a Gold Medal.
Full Defense (10 points)	Build 50 towers of any type in one mission.
Full House (10 points)	Build and fully upgrade each tower type in one mission.
Full Potential (10 points)	Win a chapter 4 (or later) mission with level 3 towers only and no selling.
Go Team! (10 points)	Earn a Gold medal in a Coordinated Defense Multiplayer Mission.
Go To Your Home (10 points)	Use the Core Teleport special weapon (Professor Taylor).
Great Ball of Fire (10 points)	Build 100 Meteor towers.
Gun Crazy (30 points)	Using only Gun towers, Win any chapter 4 (or later) mission.
Happy Returns (10 points)	Recover a loose core.
Head Trauma (10 points)	Build 100 Concussion towers.
Hey! That's mine! (10 points)	Kill an alien carrying a power core.
High Voltage (10 points)	Build 100 Tesla towers.
If At First You Don't Succeed, Retry Again (10 points)	Use the reload checkpoint option five times in a single mission.
Indecisive (10 points)	Sell 10 towers or more in a single mission.
Kaboom! (10 points)	Build 100 Cannon towers.
Leadhead (10 points)	Build 100 Gun towers.
Liquidator (10 points)	Sell 10 towers.
Master Builder (10 points)	Use the command shuttle to move 6 map sections in Mission 6.
Master Siege Breaker (55 points)	Survive 100 waves on any Super Grinder challenge mode.
Master Strategist (100 points)	Earn 100 Gold Medals on any missions.
Minimalist (10 points)	Using only level 1 towers, Win any Chapter 4 (or later) mission.
More Please (10 points)	Use the Resource Reinforcement Special Weapon (Professor Briel).
No Fast Blast (10 points)	Use the Temporal Cannon Special Weapon (Colonel Rissler).
No Sale (10 points)	Win any mission without selling any towers.
Not So Fast (10 points)	Build 100 Temporal towers.
Now With Sprinkles (10 points)	Enable a Tower Augmentation item on any tower.
Penny Pincher (10 points)	Win a mission with at least 5,000 resources remaining.
Pew Pew (10 points)	Build 100 Laser towers.
Planet Defender (30 points)	Earn a silver medal (or better) on all missions in the Story mode.
Pumped Up Towers (10 points)	Use the Tower Overcharge Special Weapon (Advisor Zacara).
Retry (5 points)	Use the Reload Checkpoint option.
Salvage Rights (10 points)	Kill an alien boss creature. (Juggernaut, Rumbler, Turtle, or Crasher)
Shell-shocked (10 points)	Using only Cannon towers, Win any Chapter 4 (or later) mission.
Shoot That Guy (10 points)	Use the Precision Targeting Special Weapon (Rear Admiral Phillips).
Siege Breaker (55 points)	Survive 100 waves on Grinder challenge mode on any mission.
Surplus (10 points)	Win a mission with at least 1,000 resources remaining.
Thanks for Playing! (5 points)	Earn a Bronze (or better) medal in a Single Player Mission.
The Not-So-Friendly Skies (10 points)	Build 100 Missile towers.
The Path Most Traveled (10 points)	Win a Gold medal on Mission 19 without using the Command Shuttle.
Tower Expert (10 points)	Build every tower and every upgrade for each tower.
Untouchable (30 points)	Beat a Chapter 4 mission or higher with zero cores captured.
Warning Shots (10 points)	Play a DG Fighter Multiplayer mission.
What IS that? (10 points)	Inspect 10 aliens.
Winning Shots (10 points)	Earn a Victory in a DG FighterMultiplayer mission.
Would you like a boost with that? (5 points)	Build 100 Boost towers.
Xenocide (30 points)	Kill 50,000 aliens.
Yellow Beats Green (5 points)	Upgrade a level 1 tower to a level 2 tower.