Defense Grid 2
65 Achievements
1,000
25-30h
Full Potential
Win a chapter 4 (or later) mission with level 3 towers only and no selling.
10
4.8%
How to unlock the Full Potential achievement in Defense Grid 2 - Definitive Guide
If you want to get the 'Gun Crazy' achievement as well, only use gun towers.
Do not sell any towers as this will void the achievement. If you do sell one by mistake you can press to revert back to your last checkpoint and the achievement will still be attainable.
You need to have every tower on level 3 (Red) by the end of the last wave. Start down where the aliens spawn and make 2 red towers. This will hold them off for a good number of rounds.
Next make 3 or 6 towers in the 'U' shaped section to the right because there will be waves where the enemies have dropships that land directly on your cores. To be extra safe put in at least 1 red tower near the exit as soon as possible.
By wave 21 I had every single space filled with red gun towers. By the end I had 18k resources to spare.
If you manage to do this without losing any cores, you will also get the 'Untouchable' achievement for 30G.
Doing it this way meant that I also got the Master Siege Breaker achievement and also the Gun Crazy achievement at the same time.
I have included a video of me completing this below if you would like some more guidance
The first mission of Chapter 4 is mission 12. Beat this or a later mission and end it having only fully upgraded towers for this trophy to pop.
The easiest mission to obtain this trophy in is mission 19 called ‘Out of Control’. Play in training mode on the easiest difficulty setting. Now lead the enemies in only one direction by blocking their paths with towers. You can use any towers you like, but personally I just used laser towers. You get enough resources to build and fully upgrade at least 25 laser towers, which should be sufficient to kill all enemies and win the mission. For visual aid please refer to the video below.
This achievement requires that you win any Chapter 4 or later mission with only level 3 towers on the map at the end of the game, and without having sold any towers along the way. While most of the maps can be won this way, the easiest approach is likely to play Chapter 19 in Grinder mode on easy and play only Gun towers. After you reach wave 10 and have a stable path, upgrade all of your towers to level 3. From that point on, don't place any towers unless you have 700 resources available, and immediately upgrade them to level 3. Note that you do not need to get a gold (or any) medal to unlock the achievement, you merely need to finish the game with at least one core still on the map.