As you grapple up onto the ship, you will find yourself looking at an Armory Reactor straight ahead. Head towards it and activate it if you want a free consumable. Grapple up to the next walkway above and blast the controls to the right. Then grapple over to the other side and use the Teletraan 1 store if you need any upgrades or have cash to burn. Turn to the right after using the store and grapple up to the narrow walkway ahead. Drop down on the other side and blast the Autobot in front of you. Head up the left side of the room, using the crates and boxes for cover to blast the enemies on the right side of the room. Loot the area for weapons, ammo and cash before moving on.
Look up to find the next grapple point. Grapple up there and you will encounter more enemies at the opposite end of the walkway, two armed with rockets and one with a shotgun. Take out the Shotgunner as he rushes towards you, and then aim across at the guys with the rockets to eliminate them. Head across to the other side and hit X to plant a charge on the door. Back away a little and let the charge do its work. You will find yourself on the outside of the ship. Look to the left to find some crates with currency in them. Pick it up and then grapple up to the floating platform ahead. Use your grapple to head up to the next level, and then proceed around the semicircle and up to the above floor.
Head around the corner and grapple the red button across from you to activate a walkway leading to the next area of the transport. Rush across the walkway as it emerges from the wall to your right, and blast the enemy on the other side. Grapple down to the lower floor and using the walls and crates for cover eliminate the enemies on the lower floor. With them gone, you can feel free to grapple back up to the top floor and waste the rest of the enemies waiting for you up there. There shouldn't be many bad guys left at this point, so this should be simple.
With all of the enemies dead, pull the level in the lower center of the area. This will open up the artillery cannon's ammunition supply. Use your grappling hook to wrench open the doors to the artillery cannon's armory. Blast the ammo inside to send that side of the cannon up in flames. No matter which side you attack first, this will trigger a stream of enemies to come out of both the left and right sides of the upper walkway. Retreat to either the left or the right side of the lower arena and let the enemies come to you, picking them off one by one with headshots as they do. When all of the enemies are gone, use your grappling hook to open up the other side of the cannon and blast the ammo inside to send the whole thing up in flames.
With the cannon out of commission, grapple up to the left and access the store. Wait for the jets of flame below to stop, and then jump down and grapple over to the platform at the last second. Blast the enemy as he comes around the corner, and round the corner yourself. You will reach a large wall ahead that looks kind of like the front grill on a car. Stand by and observe the wall for a second; you will see the gaps in the wall turn first red, and then bright orange. When the wall is orange, it will kill you with heat. Wait until the gaps turn black again, and rush across.
Wait until the flames ahead subside, and then grapple over to the next platform. Do the same at the next platform. On the other side, you will find quite a fight waiting for you. A few enemies will attack you from your level, while numerous others will attack from the above levels. It is to your advantage here to get to higher ground. Use the grappling hook to this end to grapple up to the highest level, from which you can shoot down upon the unsuspecting Autobot minions below you. You will ahve to dea with the few enemies on the top level first, though.
Midway through the battle, the Combaticon's dropship will emerge to the back of the area. Grapple onto the ship and quickly jump into its massive gun. Take out any remaining ground forces before focusing your fire on the large cannon ahead. yYou will have to use the shoulder buttons to control strafing while firing with the triggers. Strafe constantly to avoid the oncoming fire from the artillery cannon, and always be firing your gun to take out the enemy emplacement quickly. At this point, you will combine with the other Combaticons and form Bruticus.
The level from this point out is more or less a cakewalk. Hit the B button to smash enemies below your feet with melee attacks, and hold the RT to spout deadly fire from your flamethrower. Finally, when the cooldown is done, hit RB to activate a super powerful shockwave attack. You can even shield yourself by holding LT, although you will probably find this to be largely unnecessary. Simply pound and burn your way through the enemies below you and make your way towards your objective. Take out as many enemies as you can along the way. Smash through any physical obstacles in your path, too; Bruticus can bust up almost everything in the environment around him. When you reach your objective, the large, spinning turbine in the back, you will have to smash or burn it until it explodes, opening up a path for you ahead. Proceed through the gaping hole that now sits where the turbine once was. Take out the turret immediately on the other side. and make your way to the opposite side of the arena. Smash the console here, crushing any opposition along the way. This will end the current mission, and with a bang, too. The transport will go down with the inept Combaticons at the controls, paving the way for an Autobot comeback.