Grenadier

The main role of the grenadier is to shoot explosives at infantry. This is especially useful when there are clusters of infantry or the infantry is hiding in buildings / behind cover.

The smoke grenades can be used in numerous useful ways such as blocking chokepoints, revives, screening vehicles, screening machine gunners, screening towers. The grenadier smoke seems to be way stronger than handheld smoke grenades.

Grenadiers specialize in killing targets that you can't directly see. Grenadiers rely on their squadmates to designate targets ("Grenadier, hit that far left window, second floor!") so they can use their grenades to destroy enemies in hiding.