Flame Man is the one of the two Robot Masters you'll want to take out first. If you go after Plant Man first, you'll lack the Rush Power Adaptor, which comes in handy more often than not. So, Flame Man's 'Oil Field' is the best place to start. As you might realise, there is an abundance of oil, but also enemies that interact with it in different ways.
Stage[edit]
This is a fairly standard stage split into two areas, but there are some things you need to be aware of in order to stay safe. First and foremost, there are oil pits throughout the stage. The oil will slow you down but you can move through it safely. However, there are Fire Tellies that drop fireballs throughout the stage. Flames that hit oil pits will set them ablaze, and burning oil is instant death if you touch it.
You start off in the above-ground area. There are a few Mets who stay still here, with safe oil pits for you to walk through. (or jump over.) If you're re-visiting, you can get a 1-up from the cracked block. If not, you need to slide under it. Don't hug the left wall since there's a bottomless pit. Go right and avoid the first Fire Telly's flames. Jump onto the platform above the spikes, shoot the second one, then head forward. Shoot the Tellies quickly and stay out of the oil, and you should be good. Grab the large health capsule, then climb the ladder.
The next screen has two Wall Blaster II, one of which is too high up to shoot from the side you enter the room. Shoot the first, go across, then take care of the second.
After you climb the ladder, you'll be introduced to Pookers, dome-shaped robots with low profiles. These odd fellows can't be hurt with normal shots, but a fully-charged Mega Buster shot will cause them to flip and blow up. If they flip into an oil pit, they'll turn into a jump-activated platform you can use to cross safely. The third Pooker is the first you can flip into an oil pit. There's a large health capsule on a platform that you need the Rush Jet Adaptor to reach. Jump the pit, then knock the next Pooker into the oil pit. You can't simply run through the oil, as Fire Tellies will ignite it.
Keep jumping on the Pooker to propel it forward, and knock the next two into the flaming oil pit, jump up from the final one when it's at the wall. Shoot down the Fire Tellies, then climb down the ladder - Remember not to fall onto the spikes!
The next screen has three Wall Blaster II. Take out the highest one, jump down between the middle one's shots to take out the lowest one, then jump back up and shoot the middle one. Take the ladder down to the next area.
The underground area is a large, dark, cavern. The first thing you'll find is a Cyber Gabyoall. These act like your standard floor-patroller enemies, but you can stop them momentarily with charged shots. Up next is a Fire Boy. They have four health points. Work your way past the next few enemies, until you get to a pit that is already burning. Jump between the platforms carefully, here, and take out the Fire Boy responsible.
Jump over the pit, and take out the Fire Boy. If you want to get the E-Tank at the other end of the oil pit. The window to do this is tight, however. There is also a large health capsule you can get to, and you'll need to take the upper route to progress. Destroy the Fire Boys and move. The next pit will inevitably be ignited, so don't bother with the two Fire Boys at the top platform. The third and fourth ones you do need to get rid of, but with some good mobility you can avoid taking damage from the flame projectiles.
Flame Man[edit]
Flame Man himself isn't too tough to beat, another good reason to go after him first. He has only two attacks: sending up pillars of flame, and shooting smaller fireballs toward you. The pillars normally come in a set of five, and you can jump over them (but not shoot through them!). They're always equidistant from one another, so it's not too tough to pick out the safe spots. The fireballs can jumped over. Just thrash Flame Man with your Mega Buster and he'll bite the dust before long.
If for whatever reason you beat Wind Man before coming here, Flame Man is weak to the Wind Storm... Which bypasses the flame pillars, making Flame Man a breeze.
Victory here gets you Flame Blast and the Rush Power Adaptor, vital for unlocking Beat and finding some hidden items.