Valkyria Chronicles is one of the best SRPGs ever made, even it being 11 years old it still manages to be fresh and a nice change of pace compared to other games of the genre.
You play as Welkin, a nature loving student who gets thrust into the horrors of war alongside your adoptive sister, Isara, and Alicia, a friend you have made before the war with the Empire tears your hometown of Bruhl apart. Along with the rest of Squad 7, your team must actively put a stop to the threat of the empire, along with growing with your friends and discovering that your people are not the only ones that have been devastated with this conflict.
Combat is simple, you have four units; scouts who can move around the map the most and provide reconnaissance for the rest of your squad. Lancers, anti tank units that can take down the strongest and most challenging enemies in the game with proper aim and positioning, but can go down easily, shocktroopers, who can lay waste to enemy personnel but is easily felled by snipers, who are also a class on your team, and mechanics, who serve to refill the ammo of your squadmates and repair the two tanks that are on your team. If the Edelwiess, the tank housing Welkin gets destroyed by combat or friendly fire, or the enemy squad takes your camp, it's an instant game over.
The real twist in Valkyria comes in the execution of the gameplay. Instead of pointing your characters on where to go, you can control them freely on the map. There's a meter that dictates how much your character can move, and it's a battle of efficiency to figure out the best course of action that puts your units in a advantageous position which does not result in them getting intercepted by the enemy. Depending on the unit that you pick, some units can move farther than others, with scouts being the best movement-wise, and snipers being the worst.
Along the maps there are tons of places to take cover, sandbags, destroyed ruins of buildings, and even the natural terrain and tanks are perfect to take cover with. Depending on the type of terrain you're near, you can use it to your advantage. For example, positioning your snipers nears nests can enable them to climb them and shoot from across the map with precision. Laying units in tall grass can hide them and can make them invisible to passing foes, or provides reduced damage when found. Squad actions take command points, which means you can use the same units over and over, however their movement meter will be more and more stunted to avoid exploitation.
You can also take over enemy encampments, which then serve as a center where you can make units retreat and call in reinforcements when you're running low on units. Make sure you're defending them properly however, because the enemy can take them back.
There are also special enemies that should be priority number one on a map if you can discern them, these are commanders. If you kill them, it knocks one point off of their command points permanently, which makes them move less in the battle overall.
Welkin can also provide orders from his tanks, which can change the stats of the squad and save them in life threatening scenarios. You'll be using them quite often but make sure to keep an eye on the command meter since orders use them too.
When an ally falls during combat, there is a 3 turn limit to get to them with any unit and send a medic. If you do not make it there in time, the unit dies and you can't use them again. Some units which are important to the story, like Alicia and the central members of Squad 7, are commanders as described above, which makes them retreat and not die, but at the cost of a diminished command meter since they hold points.
That said, while the game is simple, and the maps provide unique challenges every chapter, sometimes the difficulty spikes can be absolutely insane. For example, I was stuck on Chapter 17's battle for a good 3 weeks, and managed the finish the game easily when that was beat.
Additionally, to counter that you can go train your troops with XP and money gained during the battles, which allow you to make them elite troops with more damage and abilities. You can spend the money in the R&D department to upgrade weapons and tanks, and you can also spend money on newspaper articles which unlock additional side stories that you can play through for extra goodies. Along with that are skirmishes which can absolutely be exploited to hell to make your units walking tanks. While the game may be difficult at times, it provides more than enough to make sure you can see the story to it's conclusion.
Speaking about the story, you'll come to love the world of Valkyria Chronicles, the characters go through significant character development, and it feels like you grow with the squad the more and more you play with them. The ending to the story was simply perfect, and was the main factor that I plowed through this game with.
The game will take you a bit to go through properly. I cleared the game within 27 hours, however you can easily hit 30+ if you want to do everything.
This is an easy recommendation, and it's pretty cheap on Steam, PlayStation Store, Xbox Live, and Nintendo eShop. Play it ASAP.