armored valkyria: shadow of the enders descent
1) Armored Core: For answer
2) Valkyria Chronicles
3) S.T.A.L.K.E.R: shadow of chernobyl
4) Zone of the enders: the 2nd runner
5) Descent
a mecha based 1st person shooter/tactical RPG set in space, which sees you and some pals comming across an advanced giant robot, taking it, and dealing with a threeway battle between humans, humans using automated machines and liquid metal aliens, in between shooting stuff you have to recruit additional troops to help you in combat as well as upgrade and look after them (once that unit dies they're gone for good) alongside upgrading and refitting your mech and doing odd jobs for cash
gameplay and combat is a mix of S.T.A.L.K.E.Rs FPS combat, Z.O.E's melee system, and descents 6 directional movement physics thing, and in a command screen you pick your troops and move them about 3rd person shooter style (however they don't actually begin moving in real time until you've exited the command screen, taking out the turn based element, while giving you some breathing room)