Defense Grid: The Awakening was released back in 2008 when standalone TD games were new rather than just being minigames inside of StarCraft, WarCraft 3 and perhaps tacky flash games. Defense Grid has the typical gameplay you would expect from a TD; place towers along various arenas to shoot creeps as they try and escape to the end.

Firstly, if you're absolutely new to defense grid or tower defense, I recommend playing the first couple levels of this game, and/or doing a quick google search about what a tower defense is. This guide will assume you have played either some defense grid or some flash games or mods that will give you the basic principles of a tower defense game.For those familiar with the genre from mods/maps in other games, or flash tower defense games, Defense Grid is different from other tower defense games in two key ways:. My house 1 hour. Cores. Interest. How cores make defense grid differentIn most tower defense games, you are 'hurt' or simply lose when an enemy leaves the playable area or reaches some other destination. In some, you'll have a key structure that enemy waves will attack, and you lose when that structure is destroyed.Defense Grid has the rarest mechanism for losing: enemies ('aliens') have to carry items ('cores' in Defense Grid) to the exit. This will sometimes be the same location as the entry.

If an alien picks up a core and is destroyed, the core will float back to the housing. (With the exception of flying aliens. All cores they swoop away with are lost forever, so they need to be destroyed before they reach the housing)This means that the aliens will often have to turn around and go through at least some of your previous towers, or they'll continue on to the end of the map, giving you some 'slip' room, but also meaning you have to be careful that an alien doesn't escape with a core by picking up one that's still floating back to the housing. Interest and coresNot only do you have to avoid losing all your cores to win the map in Defense Grid, and not only do you need to keep every single core to score above a bronze medal, you also lose out on interest while cores are outside the housing.Unlike most tower defenses, you earn interest on your cash ('resources') if you don't spend it. This means that there will be a bit of adjusting if you play other Tower Defense games without interest- once you can complete a level with all your cores intact, the goal then becomes to score as high as possible by spending the least on towers while also keeping the cores in the housing.If you're just interested in completing the maps, (ie.

Achieving a bronze medal) you probably won't need this guide for anything but the most difficult maps. But understanding how to use all the towers most effectively and understanding how to play with interest is often necessary to achieve gold medals, and it's crucial to achieving higher scores.

Maps and modes drastically alter how the game is played.Here's a list of different situations to watch out for in a map:. Entrance and exit are the same place, making the map a 'loop' for the aliens. The exit is in a different place than the entrance, making at least part of the map 'spillage', where only aliens carrying cores will be moving. Some maps are 'on rails', with the aliens on a set path and all the buildable areas away from that path. The only way to slow aliens on these maps is to use the temporal tower effectively. Some maps will have flat areas that are partly or entirely buildable, which allows you to shape the aliens' path, ('mazing') or will have buildable areas that can block off certain paths.

Some maps will have multiple entrances or exits. I can only think of one map where it's not practical to redirect one of the paths into the other one. This is more hectic/difficult to manage, but it also allows you to use each of your kill areas afterwards for both sets of aliens. (spoiler: Infiltration is the map I'm referring to).

Some maps will have paths for flying aliens - press 'T' for an outline of these, and a reminder of the entrance(s) and exit(s). Are there multiple core housings? Some maps have two. In some of these the cores are split, in others the cores move. Are all your cores missing at first?

You'll need to kill the first wave of aliens for them.Some more in-depth tips about utilising the map: when you can maze in relatively large areas, create areas where the aliens have to perform u-turns in front of particularly damaging tower formations. This allows you to utilise laser and concussion towers most effectively.

Creating areas where you can focus a lot of area damage and single target damage at the same time makes an effective all-around killing zone, especially if you can utilise longer ranged towers in other buildable areas.When you're making a maze, make sure that there always is one route to each active core housing- the aliens will start walking through your towers if you block it off entirely. Aliens can only walk diagonally on buildable areas where you leave open multiple edges from their last tile, which will make it more easy to block some paths, but it also makes it easier to accidentally block them off entirely. You can safely block off core housings that the cores have moved out of. JugglingIt's possible to identify a key tower that can be sold and rebuilt to cause the aliens to turn around on a path.

Because you lose money by building and selling towers, there's a certain element of strategy to using this method, but there is a measure of debate among some people in the community if it's legitimate. The developer doesn't consider juggling cheating or exploiting and it won't be patched out of the game. That said, I don't use this method, so I can't advise you on how to do it effectively. You'll need to look for a juggling guide if you want to top the score charts on some levels, and you enjoy playing that way.

Aliens in Defense Grid come in six essential varieties, although there are some additional variations with stronger aliens or that can share their special abilities. I've listed the alien names after each type, in order of general difficulty. Normal aliens.

(Drones, Swarmers, Walkers, Rhinos, Crashers). Fast aliens. (Racer, Rumbler). Shielded and shield-sharing aliens.

(Bulwark, Spire, Juggernaut). Cloaked and cloak-sharing aliens.

(Lurker, Decoy). Aliens that spawn other aliens.

(Seekers and Turtles). Fliers.

(Dart, Manta)Normal aliens are relatively simple to deal with, you place the optimum tower for each spot as necessary and upgrade as necessary, and watch them die. Essentially normal aliens can be subdivided into waves that are effective to kill using AoE towers (early on in a map, that's only the Swarmers) and ones that require single-target damage. With upgrades, Walkers or even Rhinos can be practical to kill en masse using Inferno and Concussion towers, but Crashers will always require a lot of single-target damage.Fast aliens are best killed using burning damage, so you'll want inferno towers and sometimes laser towers to combat these, and you'll want temporal towers placed in the areas you're applying your burning damage.Shielded aliens need the opposite approach- they are immune to burning damage until their shields come down. If you have enough space, this means you can just use a lot of impact damage towers before applying your burning damage.

Spires share their shields with anything nearby, so concussion towers are especially effective against them if there is a good opportunity to build one.Towers can only target cloaked aliens from very short range unless the aliens are in the range of a command tower. It's generally a good idea to build one for cloaked aliens, but Inferno and Concussion towers are very effective against cloaked aliens if you place them properly.Spawning aliens are essentially just a tougher, slower version of a normal alien at first, although they can spawn any ground alien. Seekers will wait some time then start deploying a stream of aliens as a kind of forward shield to distract your defenses from themselves, wheras Turtles are tougher and spawn a set payload on dying. Trickier levels will have these aliens deploying Rumblers, Decoys, Spires, and other nasties, which means the middle or end of your defenses will need to be quite deadly.Fliers are rather straightforward to dispatch. They can be killed by gun towers or cannon towers if they conveniently fly in range and your towers aren't busy with ground enemies, but generally you'll want to put a missile tower or a few in their path somewhere that isn't needed to kill ground aliens.

You'll usually only need one or two level one missile towers to kill darts, but if you get mantas instead or as well, you'll want to have your towers upgraded to second or third level.Congratulations, you now know the basics of Defense Grid- with a bit of initiative this much will be enough to bronze medal the entire Awakening campaign. But if you want gold medals or to play the harder campaigns, read on. Gun Tower100 / 200 / 400 resources, 700 total to level 3Purpose: Mazing (level 1), removing shields or close-ranged damageOptimal placement: Anywhere where its line of sight isn't blocked by other towers.Especially effective against: Drones, Walkers.Bonuses: Can assist with fliers.Use gun towers either to shape the enemies' path when you can maze, as they are the cheapest tower to use as a wall. Because of this, they do less damage at level 1 than other towers, so upgrade them as soon as practical when you plan to use them to do short-range impact damage, or to remove shields. 275 / 550 / 1100 resources, 1,925 total to level 3Purpose: Area of effect impact damage and area shield removalOptimal placement: Areas that aliens turn around. U-turns, three-quarter turns, or perhaps in a zig-zag turning pattern for two-wide paths)Especially effective against: Spires, Seekers, Bulwarks, Swarmers, Walkers.Bonuses: When placed correctly this tower is really good against anything, but it excels at removing shields from groups and killing weak aliens.The concussion tower is a bit more specialised, but there are more opportunities to use it when you've got a lot of space to maze in than there are for the Inferno tower, and less opportunities when the enemies are on a fixed path.

It and the inferno tower are the ideal towers to emphasise for Grinder mode.(Pictured: the ideal placement for a Concussion tower). 250 / 500 / 1000 resources, 1,750 total to level 3Purpose: Long range area of effect damage, mostly burning but some impact, backline tower.Optimal placement: Any area that significantly overlaps your maze.Especially effective against: Swarmers, Seekers, Decoys, Lurkers, Turtles.Bonuses: This tower will slowly take down shields if it targets shielded enemies, but don't rely on this to remove shields effectively. The tower can be put in a lot of the reject areas that have next to no line of sight, as it fires in an arc and can be effective in most positions.Because it uses a ballistic trajectory, it is an excellent backline tower. 225 / 450 / 900 resources, 1,575 total to level 3Purpose: Long range damage against fliersOptimal placement: Any area that significantly overlaps their flight path without effecting the rest of your defenseEspecially effective against: Mantas, dartsBonuses: Against most dart waves you won't need to upgrade this tower. The last Awakening map has so many darts in a single wave that you'll need to upgrade a tower or build a second just to deal with all the darts- otherwise I'm pretty sure a single level 1 missile tower will be sufficient unless the air icon goes yellow in your wave indicator.

175 / 350 / 700 resources, 1,225 total to level 3Purpose: Spillage control, builds up a charge over time for a large burst of damage.Optimal placement: Near the exit on maps with spillage areas or at the end of your maze.Especially effective against: Crashers, Juggernauts, RumblersBonuses: Can hold a longer charge as it upgrades as well as improving continuous damage.This tower should really only be used to mop up stray aliens, if a large number of aliens are passing it, then the Tesla is no longer effective. 200 / 400 / 800 resources, 1,400 total to level 3Purpose: Short-range burning damage to a single targetOptimal placement: Front-row positions in your maze or areas that tough, unshielded aliens will be turning around, or where the path is too far away for a concussion tower.Especially effective against: Crashers, Rumblers, Turtles.Bonuses: The burning damage applied by multiple towers can stack to some degree, although aliens have a maximum 'heat' level. Essentially you'll want to space these so that tough and/or fast aliens are burning a lot.Laser towers are mostly only necessary when you're having trouble killing rumblers or crashers, but can also very effective against juggernauts when their shields have already been removed.

Good point about selling towers before the end of the game to get extra interest, but there's a 'gotcha' on maps that have a very long path to the core housing - you stop earning interest after either a certain period of time after the last wave enters the map, or an alien in the last wave carries a core close enough to the exit. So, it's a balancing act to do two things: Weaken your defenses so that one or two aliens actually grab a core, leaving just enough to kill it before it leaves, and do all of your selling before you stop earning interest.