I hid behind the pillars and used a sniper rifle on Frenzy, Rumble and Laserbeak. It takes a ton of damage. Make sure you stay away from Soundwave when he runs out the heal his kids. He'll come at you with a melee attack.

 

I'm not sure it makes a difference, but try to aim for the heads of Frenzy and Rumble. I think that did extra damage. And Lazerbeak, when i was behind a pillar won't fire at you 99% of the time. At least he didn't when I fought him on hard.

 

When you get to Frenzy (Frenzy's the second cassette that attacks you right?) try to stay at a distance from him because he'll melee you, and watch out after you shoot at him for a bit because he'll come at you

 

Prime's Warcry also helps a lot during that fight if you aren't using it already. I generally stay behind a pillar shooting each cassette with the Assault Rifle or Ion Blaster and moved away to the opposite side of the room if they got close.

 

Also of great help is the Thermo Rocket Launcher in the outer room, along with the grenades. The Thermo automatically tracks Laserbeak so it makes that part easy, and if you are a good shot you can really do some damage to Frenzy/Rumble. The only reason this works is because the ammo keeps respawing in the middle of the room.

 

for frenzy and rummble i didnt even bother shooting them, i just melee them to death. of corse rumble is a pain so i hide behind pillars until after he does his attack. as for laserbeak, yeah hide behind pillars and snipe. as for soundwave i use vehicle mode weapons

 

It took me a long time to beat Soundwave on Hard!

Use the rocket launcher on all three minicons. Get to cover behind one of the pillars when they shoot and unload with the rocket launcher every chance you get.

When fighting Laserbeak, you can actually hide behind the back left pillar (as you enter the room), and he will just hover in place on the far side of the chamber. You get lock-on, peek out a bit, and shoot him. The only time you have to leave cover is to grab the ammo in the middle of the room.

 

I used Sideswipe, and picked up the rocket launcher before going into the room. Frenzy and Rumble are a pain in the arse, but you've got to keep them at arms length, and batter them with rockets. Laserbeak is a piece of cake with the rocket launcher. I found this the hardest boss on Hard difficulty, Trypticon was considerable easier.

 

As everyone said, pick up the thermo rocket launcher. Makes the fight much easier.

Frenzy and Rumble: The best thing to do when against both of them is to keep your distance and keep moving while attacking them with the rocket launcher's splash damage. Getting caught in Frenzy's rage lunge or Rumble's shockwave means you loose a conciderable amount of health.

Laserbeak: While he's an easier target those laser blasts can cut you down in no time. Hide behind one of the pillars opposite of the side that 'Beak is on. When out if his sight he'll just float there for a bit before switching sides. Lock onto him with the launcher and blast him out of the sky while switching pilars if needed.

Remember to use either Bumblebee or Sideswipe, who's abilities are perfect to use against the cassettecons and Soundwave and keep an eye on what the turrets drop when they're destroyed. Energon bits to replenish abilities, ammo chips and energon cubes are all dropped, so keep yourself juiced between minion battles.

 

I played optimus with warcry on co-op. popped a warcry and used an energon pistol to take shots at the little ones. HIDE BEHIND THE PILLAR WHEN LASERBEAK COMES OUT. that is all  

 

I soloed the hard campaign and bosses...

A few things to keep in mind:

1. if you see a floating ammo or energon health cube that you DID NOT break open from a container, it will respawn every 5 mins or so.

2. I would advise you learn to hold the controller with all 4 top buttons of the controller with your finger on them at ALL times. ex: both pointer fingers on L1/RI (LB/RB) and middle finger on L2/R2 (LT/RT).

Omega Supreme final fight: I use anyone:

-when he is firing his rockets and his arm cannon I transform and drive around in laps around the arena and colect ammo and health
-when he's finished I open fire
-repeat

Starscream: I use Optimus:
-use the rocket launcher and the lock on for his jet mode
-When he's in his bot mode hovering I double jump and melee him
-when he strafing around the area I use Prime's Ion Blaster
-repeat

Soundwave and bots: I use Optimus and pick up the rocket launcher.
-Frenzy I always jump back and fire a rocket at the floor in front of him because the splash damage hurts him.
-Rumble, same strategy as Frenzy but I double jump back because the pile drivers will mess you up!
-Laserbeak I use the rocket launcher since it always locks onto him.
-When Soundwave comes out to heal his bots I wait for him to have his back toward me and I melee with Prime's axe as fast as I can, I normally can get him to recall his bot he healed before he returns back to his shield room.

*NOTE* If you wait for Soundwave by the shield when he drops it, he WILL melee for a lot of damage! Wait until he is a few feet away and hit him from behind and keep meleeing him!

Trypticon: I use Bumblebee. This fight seems tough on hard because he does so much damage, but it's easier when you learn his patterns! Always keep moving, I can do this fight solo and not get hit.. yes on HARD! I stay in the lower floor,
-when he fires his tail rockets I drive in large circles. (only time I use alt mode, because Bee is super quick)
-When he is going to strike with his tail, look up and his tail will glow when he is about to strike, he will strike left, right or middle. Start using LB/LT dash to get to the other side of the map of where he is going to strike, also double jump as the tail is about to hit the ground if your not far enough to the side of the middle strike to avoid the splash damage.
-When he is about to use his breath fire, walk to the far left side and just simply walk right, when you reach the end of the area, double jump and boost left and when you land walk left, easy as pie.
-repeat

Learning the patterns like old school Megaman games is the key for the boss fights, and fast reflexes, which is why I advise you keep the shoulder/top buttons with your fingers on them the entire time you play!