After the beginning turn left and approach to the golden box. Melt it using a fire beam (Human Torch have something like it) and then use a computer.
To obtain next minikit, you must destroy five Magneto statuettes located in this room. First of them can be found on the wall near to the violet power field.
Second one is attached to the wall on the far right.
Third is hidden on the left from the exit, in the upper corner.
Fourth statuette can be found on the right from the strange machine that should be destroyed during the walkthrough to the next part of the level.
The last Magneto figure is placed in the platform on the right from the huge turbine.
Go to the exit door from the first stage and turn left. Choose Magneto to manipulate a metal box, so you can uncover a minikit.
After starting the fire at the highest floor of the stage (see chapter: Walkthrough: A Doom With a View) approach to the flames with Iceman and extinguish them. Now you can pick up a minikit.
To obtain the last minikit in this room you must start a fire on the highest floor first. After that, defeat all enemies and destroy a silver plate using Iron Man's rockets.
In the room with a huge gate (with the space abyss hidden "inside") turn left and yank two green handles using a big character.
On the opposite side of the same room a pile of sand is hidden. Dig up a minikit from it, using Wolverine or other clawed character.
Go to the left side of the room and fly to the windowed room located above - a minikit is floating there.
Melt a golden wall under mentioned room using a fire beam and then melt a golden monument.
During last fight with Doctor Doom turn left and fly to the silver plate as Iron Man. Shoot at it using your rockets to unlock some black cosmic bricks. Construct a box from them, using Galactus super powers, and wait for minikit to appear.