The Fire Assault is a rather durable but slow moving infantry unit that specializes in diving head first towards the enemy with their Jetpacks to quickly dispatch lightly armored combatants in a sea of fire.
Very high damage output against large groups of infantry and light vehicles
Can detect enemy units hiding in forests
Can jump up or down cliffs if enemies are in jumping distance
Extremely durable for infantry standards which allows them to soak up a lot of damage
Slow base movement speed
Very short attack range
The usage of the Jetpack cannot be controlled and is therefore unreliable
Will struggle against units that far outrange their jumping distance like snipers
Vulnerable to bullets while in mid-air
Fire Assaults will be at their most effective when fighting large swarms of infantry and should be primarily used if you know your opponent will be focusing on large amounts of infantry as they are a fairly costly investment early on due to their level 3 Barracks requirement in addition of being the most expensive confederation infantry unit in general.
While having a very limited attack range and moving slightly slower compared to Assaults, they make up for these weaknesses in combat by utilizing their jet packs to quickly close the distance when within jumping distance of their enemies. This jump propels them so fast that they can even catch up to Jaguars and reveal them while hidden by Chameleon. For them to jump at least one unit has to first be revealed though, as manually jumping is not possible. Good units to reveal that initial unit are Assaults, Cyclones and Cerberus.
This ability also allows them to jump over cliffs, walls and other obstacles like trees or rocks. Additionally, they come equipped with sensors that allow them to spot units hiding in forests, making them excellent in clearing out infantry infested forests in a matter of seconds. While jumping they are only vulnerable to bullet based attacks, and all other attacks will not target them.
Additionally when used in tandem with Hammers or Zeus, enemy units and defenses may automatically target the Fire Assaults instead of the tanks, which can potentially tip fights in favor of the confederation units even if outnumbered provided the opponent doesn’t micromanage his units correctly, as Fire Assaults are very tanky and can soak up a lot of damage.
An advanced strategy is to use them in a sort of scare-tactic. For this to work, a player lets them run into a Chameleon cloud, which will cause the enemy to retreat backward in most situations. This means, they allow for a very short-term, but also very accurate prediction of where an enemy army will be going in the future as retreating usually means, straight back where the units came from. At this position, a strike with Thor or even a Space System can be aimed, to try and deal enormous damage to the army.
Trickery like this only works once or maybe twice per battle though, so it's important to immediately switch into very aggressive gameplay after succeeding.