Saint George is that hardest achievement to get in Planetfall: Age of Wonders, but it is actually pretty easy. You have to kill a Savage Tyrannodon with an Oathbound Paladin Aspirant. Not that a Savage Tyrannodon is different from the Tyrannodon in the Amazon tech tree since it is not a mounted unit. What makes this different than some of the other achievements that involve killing units is that it also has to be an enemy savage Tyrannodon.
You can get this achievement easily in Galactic Empire mode after having unlocked the Paladin Aspirant and a number of other indirect fire mods for requisition. When you go to conquer a new world, you need to choose an Amazon commander, select the Paladin Aspirant as a unit you will be able to use requisition points for (it will only cost 100), and then choose offensive mods to be available for requisition as well. For this, I chose Maxwell’s Puzzle Box, the Sequential Kill System, and the Positron Arc Projector. You can choose not to have these mods, but it is hard for the Paladin Aspirant to have the attack power without the attack buffs they provide.
When you get into the game, keep researching through the tech tree until you get “Restorative Cloning” which gives you access to the “Clone Predator” Strategic Operation. Keep using this operation to spawn Tier 3 predators until you get a Savage Tyrannodon in your army. The operation costs 200 energy pop and the unit you get is random every time, so it took me 14 tries before I finally got the Savage Tyrannodon.
Leave the Savage Tyrannodon completely unmodded so it can be taken down easily and bring it with one of your armies that also includes the Paladin Aspirant. Look around the map until you find a wildlife encounter that contains unit E: Bot Emma-3.
When you get to this encounter, choose tactical combat. Run the Savage Tyrannodon straight towards the Emma-3 enemy unit. Emma-3 should use the Love Pheromones ability and mind control your Savage Tyrannodon. At which point the Savage Tyrannodon becomes your enemy and you just need to make sure you get the killing blow with your paladin Aspirant.
And that concludes this Age of Wonders: Planetfall guide. Help us improve this guide by leaving your suggestions in the comment section below.