Contra III: The Alien Wars/Stage 1: The Streets of Neo City

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Ah, the sights to see in the ruined city. Watch out for the dogs eating from the trash cans ahead. On the higher difficulty levels they will run at you after you pass by them. Jump into the tank when you see it and start some carnage. Blast the walls with the turret and watch them crumble down. There will be another one ahead. Once you reach the spot where the flames are shooting up out of the ground, you'll have to get out of the tank and head off on foot again.

Jump over the bunch of them and grab the powerups if you want. Further ahead, the wall will crumble and a tank will come out.

Magnetic Armored Tank Magnus Mk. II: This boss is simple to defeat, just pull out a weapon and let her rip. You should be able to destroy it quickly, usually before it reaches the side of the screen. It won't be able to reach you there if you're right in the corner though.

Jump onto one of the platforms when the bomber comes and blasts the ground. Keep going right, avoiding the flame balls and pillars of fire. A few times here a pillar of flame will twist over the top of one of one of the platforms. Stay still until it goes away. Continue on until you see the boss and make sure to grab the Aura Bombs on the platforms there.

Beast Kimkoh: Stay on the bottom and start firing at the flashing lump on its chest. The boss will fire a huge laser out of its mouth once in awhile, followed by a stray bullet so you have to jump to the higher platforms when that happens. You can tell it's about it fire the laser when its mouth starts flashing. Shoot the fly enemies that come out of the top of the boss's shell if they start bugging you, otherwise just blast its chest until it dies.