Sledge
Rook.
Sledge is great because his ability alone encourages exploring around and getting a better understanding of what is breach-able, where in a map. Because not every wall/floor is able to be breached but his hammer has multiple utilities. It can knock any door/window that isn't reinforced down, he can destroy barbed wire in a single shot, it's substantially more quiet to use his hammer to breach than pretty much any other option and his hammer makes a great weapon for sacrifice on a downed enemy, boosting team morale and lowering your enemies. Sledge imo, specializes in flanking the enemy quietly. Best utilized right as the primary team attacks an objective. A good tip for brand new player is to play T-Hunt on Medium/Hard with Sledge and play a few rounds on each map to learn the maps.
Rook is great because he has a ton of health and the MP5 is a great weapon and his ability can help every single person on the team without him having to do anything other than lay it down. Rook is the defender I hate fighting against the most, as when he's played by a good player, he's an incredible pain in the ass and distraction AND I know the rest of his team probably has extra armor too.
