The final Trypticon battle is really easy once you understand his pattern. He has four "attacks" that he cycles through in order.
1: Homing missiles
2: Purple fire breath
3: Tail missiles, tail smash
4: Energon crystals that burst with spiderlings
He ALWAYS does 1, 3, and 4. Attack #2 is only done occasionally.
Start out by heading to the left and taking the X12 Scrapmaker (the weapon you'll use for the duration of the battle) and the ammo. Position yourself as far left as you can under the overhang (right by where the weapon spawns), as the homing missiles will not hit you there. Next, run behind the ramp to protect yourself from the fire breath (he will always do this attack the first cycle). After he stops attack #2, transform and watch for tail missiles to appear. When you see them coming, thrust across to the other side of the map (to the right of Trypticon), up the ramp, and around to the top area, which will avoid the missiles and the tail smash. Transform and target his weak spot with a full clip, at which point he should start laughing. Don't bother with a second clip- patience is key here. Transform and thrust straight back to the overhang area in preparation of his first attack, driving through any crystals that are in your way. While waiting out the homing missiles, melee spiders as needed (the missiles will kill any that are still around). From here, repeat until he is dead. Be sure to grab ammo or health as needed.