Ironically the swarms of enemies are welcome since you can kill them for health, near the ending the mooks stop appearing so you have no way to heal yourself unless you use counter force (press B twice fast) to convert close enemies bullets into life ups (and that's is so risky you'll probably lose more health than heal it).After a while, Contra starts to look easy by comparison. Alien Soldier requires the player to juggle swarms of enemies, traps, fiendishly hard bosses, a timer that always seems too short, greatly limited ammunition, and the fact that you are vulnerable when switching between weapons.Not only there are no passwords or backup, but the continues are limited and if you lose all of your lives and continue, you start at the beginning of the world you are on, which is tedious considering how large the levels are. This game doesn't forgive mistakes, either.
The controls are problematic, and the levels are packed full of well placed instantly lethal spikes and Mine Cart Hell (or, in this case, Roller Coaster Hell) where one false move and you're dead.
Oh boy howdy, is the first Adventure Island game ever this.