Advanced tactics for Defense Grid

[pdanoe]

In this thread I will try to divulge some of the learning that I have had through the years. Hopefully someone will be able to pick up on it.

There is a lot of material out there for the beginner to intermediate player. Most players have the ambition to get gold in every map, and then that's it. A few players stayed to compete for records. This is their learning. Not much of this is recorded in videos unfortunately.

[pdanoe]

(1) Juggling technique
First off, a good juggling technique is an important point of training. There is a variety of juggling techniques, but the most usually employed is a 2 door juggle, meaning, 2 towers are alternatively built and sold. When dealing with juggling, timing is key, and it is important to time the juggling with respect to the temporal. When driving the aliens back and forth around a killzone, it is important that the temporal does its job to almost 100% efficiency. You can help the temporal tower by e.g. Observing the rule, that the temporal is best at slowing down aliens that are moving in a right angle or away from the temporal tower, whereas it is weaker in slowing down aliens moving towards the temporal.

The timing of putting down the temporal will also potentially mean a lot to the score, so if the timing of the temporal respective to an important wave is off, go back to the point where you put down the temporal, and put it a bit earlier or later. Only experimentation will get the timing exactly right there.

The recently played map Turnabout 20T is a good example of a very hard map with respect to juggling. I had to use a 3 door juggle for the hardest racer wave, wave 15. Racers will come from all 4 entrances, and doing a juggling that catches them all in the temp trap is a piece of art in my view.

[pdanoe]

(2) The Brixx79 FAQ – and choice of killzone core weapon
Someone has created a faq on the DG game with an enourmous amount of technical information. I should consider to copy paste it to this forum. But here are at least 2 locations to it:
https://gamefaqs.gamespot.com/xbox360/945048-defense-grid-the-awakening/faqs/57896
https://www.neoseeker.com/defense-grid-the-awakening/faqs/195766-walkthrough.html
One point of interest in the FAQ is the question of, what weapon to select at the core of the kill zone. Should I drive the aliens around a yellow conc, a red conc, a yellow inferno, or a red inferno.

Again, testing will tell. But for those killzones where aliens tend to group in a smaller bundle, obviously an inferno will be better. The Brixx79 faq states on the concussion tower:
Cost Range Damage
Green: 200 180 4.56/ 1 sec to all aliens in range
Yellow: 400 180 13.75/ 1 sec to all aliens in range
Red: 800 180 32.08/ 1 sec to all aliens in range
*60 range = 1 square

Comparatively, the infomration on the inferno tower is Cost Range Cone Damage
Green: 150 150 70 degree 4.17 and 0.96 heat/1 sec
Yellow: 300 150 80 degree 11.25 and 7 heat/1 sec
Red: 600 150 90 degree 23.86 and 31.53 heat/1 sec
The point that I want you to consider is, how much more powerful the inferno is compared to a concussion, if we are able to get the aliens grouped in a small group. The red inferno tower gives off 23.86 dps (damage per second) plus the heat damage. The heat damage will only work if the aliens are not shielded. Add to this how cheap the inferno tower is, that you can by a red inferno for the price of a yellow concussion plus a bit, and you will see why I so much favor the inferno tower.

[pdanoe]

(3) Inferno towers can shoot through other towers
Inferno towers is special in the sense that, even though you do not see a flame, the inferno can still be operating. The designers of the game thought it looked bad to have the inferno tower fire through other towers, but they kept the tower effectively working. Besides, the area of operation of the inferno tower is a whooping 90 degrees angle, which means 45 degrees to each side of whatever alien is being specifically targeted. In conclusion, if I am able to keep the aliens in a circle about 2 squares from the inferno, that will be the optimal setup for the inferno.

Case in point: my recent gameplay on Turnabout 20T. The inferno tower is actively targetting the aliens on the other side with both damage and heat.
https://steamcommunity.com/sharedfiles/filedetails/?id=3348265357

[pdanoe]

(4) The Orbital Laser trick
A shielded group with a spire in the middle can be dealt with using the orbital laser. You do not try to kill the spire itself (200 killpoints + command bonus = 290 killpoints), but rather you target one of the shielded swarmers (10 killpoints + command bonus = 14.5 killpoints). If just one of the shielded swarmers is hit with the OL, the shield will come off the rest of the group as well.

A link to Frengky videoing the OL trick in center of power, at the 4:52 mark. Take note that he kills a few swarmers, but the central spire is left untouched.
https://www.youtube.com/watch?v=5ThZemVz82c

[pdanoe]

(5) Floating core trick
So named by Frengky. This trick can only be performed in maps where cores switch from one corehouse to another. Meaning, only Surprise Party (in You Monster map pack), Auger (in Containment), and Polimer maze (in Community Levels) are maps, where this trick is possible. Oddly, it seems that the map designers did have this trick in mind, for at the right time to perform the trick, there appears a horde of swarmers, which can then be sent to grasp the cores and move them faster to the other core house. At the second corehouse, set up a temporary killzone meaning an inferno or a concussion (never mind the command), and allow the cores to float into the corehouse. How effective this trick is, can be see from the scores at e.g. Polimer maze, where my score in story mode is 190.9K compared to e.g. Frengky 186.8K. So at least a 3% improvement of score. I link to a video where Frengky shows a bit of the floating core trick on Auger, driving those cores to the upper platform
https://www.youtube.com/watch?v=JnagZymomU8

[pdanoe]

(6) Tesla vs shields
At one point, the tesla tower was the least used tower of all. Short range, low power etc made it a poor choice. HP decided then to give it double power against shields. So now, if you a playing a map with a lot of shields, the tesla tower will be a good choice.
Example in point, the above screrenshot from Turnabout 20T, where I use 4 green teslas because of all the shied in the map.
On a counter note however, I have not seen a map where it pays off to upgrade the tesla to yellow or red. So keep it green, and enjoy it's power against shields especially.

[pdanoe]

(7) Guns
The gun tower is a very good tower in itself, it can target also flyers etc, and has a high output against single aliens. The Brixx79 faq states
Cost Range Damage
Green: 100 210 10/ 1 sec
Yellow: 200 225 30/ 1 sec
Red: 400 240 70/ 1 sec
Not only are the upgrades cost-efficient, but they also come with increased range. A red gun will often be able to take out the first 3 waves in a map, which means you can then focus on getting up your command and other setup.

The gun tower performs better in FF (fast forward) mode, which I will explore in next post.

[pdanoe]

(8) The FF (fast forward) option
For the trained eye, the FF is not just a button to press to speed up the game. Different towers react differently to running FF. Not much, but sometimes it is the little difference that matters.

Towers that run better in FF
- the gun tower

Towers that run worse in FF
- the concussion tower
- the temporal tower
- the missile tower
- the meteor tower
- the cannon tower

Towers that have not been investigated enough for this matter
- the inferno tower
- the tesla tower
- the laser tower

It is also worth noting that aliens may take a slightly less rounded path if put in FF mode (I.e. get quicker through the killzone). It is a tiny difference, but then again, it just may be the tiny difference that matters.

[hanbaoluo]

I was told that cannon towers run worse on fast forward from takista circa August 2010. Salmusco, yangsapozol (takista) and I were competing for Containment 15 tower limit[i.imgur.com] when this topic came up. Not FF with the cannons made a significant improvement on this mission for me.

[pdanoe]

(9) The double temp
Especially with non-juggling maps, it can pay off to put up more than one temp. When the temps are next to each other, they will fire the slow weapon with double frequency, which has a visible impact on the ground units. Not one of them will take a run, and this will be useful, because you want the aliens to be in your killzone as long as possible and move as slow as possible.

This is a counteract to the somewhat stochastic behavior of the temp, where some aliens will be allowed to move unslowed, even though they were hit by the slow weapon.

When you are looking for the very top scores in a map that does not encourage juggling, consider a double temp solution. Example is from the map Center of Power Shredder. Shredders should be done with as little juggling as possible.
https://steamcommunity.com/sharedfiles/filedetails/?id=3444111745

[pdanoe]

(10) Using guns or cannons to target flyers
It has been a realization, that in nearly every case, when a map has flyers, it pays off to place yellow or red guns to target those flyers. I can mention some exceptions to this rule, where a missile can be placed really well, and conversely there is not a really good spot for flyers-targetting guns. But on the norm, this is a thing to consider for a top score.

The example given is from Center of Power story, where a line of green and yellow guns can take out all flyers in the map, and when there are not flyers, the guns can participate in the normal drills.
https://steamcommunity.com/sharedfiles/filedetails/?id=3444112880