Steel Mill
Sunshine Steel Works
Near Pittsburgh, Pennsylvania
Trains and Train Tracks
This level features a fully operational rail system - by activating the levers dotted around the level, you can make the train switch tracks an take different routes. This is quite tricky, so be careful you don't send it plunging into into the stock carriages or ir will derail and explode.
Steel Mill 1 Steel Bars
Steel bars pour out relentlessly from the mill, if you get struck you'll be set alight. If this happens, head for the water to extinguish the flames. Shooting them makes them explode, ideal for hitting vehicles about to enter the building. Try dropping a Bear Hug just inside the entrance - the blind spot may catch enemies off-guard, trapping them in the path of the bars.
Steel Mill 2 Molten Metal Pots
The large pot suspended from the ceiling will follw you around the room, tipping and dropping molten steel on you when it's overhead. The pool of steel will also home in, so don't hang around too long, unless you want to leave a fews pools as a surprise for opponents. Bizarrely, the moten steel will sometimes follow you out the mill and around the surrounding area!
Magnet
As you approach the magnet, it will take hold and lift you across the channel to dry land - picking up a couple of powerups en-route. Use this to escape from enemies in the mill when it starts to get too crowded.
Tunnels
As with other tunnels, these teleport you around the level - note that the train also uses them and can often emerge without warning.
Coal Mounds and Drums
There are usually Propulsion Units to be found on the top of these coal mounds, but they're flammable, so enemy opponents taking shots at you may end up dealing extra damage.
The drums can be shot off their supports and will roll back and forth, requiring some skilled weaving to get past.
Weapons & Powerup Spawn Points
Various items can be found Inside the steel mill, plus try jumping out of the mill onto the roof of the small building, where there usually is a wrench. Powerups are scattered periodically around the tracks and the coal mounds is a good bet for hoverpods. You might also want to check the underneath bridges for hidden powerups...