SRW is mostly a standard Tactical type game, but with a few extras. You can group units together on tiles to unlock combination attacks (for example, a Grendizer / Great Mazinger / Getter Robo G super combo).
The series is also known for its style of battle animations - like mini cutscenes, you see the character perform their attack, then see the enemy get hit by the attack. Using attacks of course you could use the regular animation system - the hit, however, is a bit more complicated, as you'd need to change the target of the attack.
Lastly, you've got systems like the Spirit system, which is a little like limit breaks, except you're in the middle of the gauge by default and certain attacks only activate when the spirit gets high or low enough. It builds up / goes down when you attack, take damage, use an item, basically doing any action causes a shift in your spirit gauge.
There are as many systems in that series as there are games though, with each new game offering up a new refinement or system. I suggest to anyone asking for a "SRW TBS" is at least specific in which game they want because of the differences and the nuances in the systems.
