This game came out for the NES in the early days when we didn't have much in the way of options for what to play. It was during the popular days of Rambo and the similarities between the two are evident. The game LOOKED like it would be a bunch of fun but for the most part this is a game that brought about rage the likes of which I think most younger, modern gamers have never experienced in their lives.
I'm not faulting the developers too much here but there was a ton that was wrong with this game and unlike today, they couldn't just make a patch and send it out to everyone for a hotfix. If a game was released with problems and sent to market, you just ended up with a buggy game and that was the end of the story
You play the role of a shirtless muscle-bound dude with a headband and there is no denying that they were definitely ripping off Rambo without having to pay any royalties. I guess the makers of Rambo simply didn't care but the ironic part of that is that there actually was a Rambo game on NES as well and good lord almighty was that game terrible.
In Ikari Warriors the problems become evident pretty early on because your default weapon is a pea shooter as you would expect. What you might not expect is that this "gun" is incapable of shooting more than a few feet in front of you. Seriously, it was almost like melee the distance was so short. Your enemies didn't face such difficulties with their weapons because they can fire all the way across the screen. The AI wasn't exactly "Johnny 5" levels so this wasn't so bad.
Every now and then you would get your hands on a tank and this was meant to be one of those "hell yeah!" moments because as you might expect, the tank is significantly stronger than your regular arms. Don't get excited. The game would cheese you every single time that you get a tank in that the enemies come at much greater numbers than they would if there wasn't a tank involved and you are going to take a ton of damage because you are now a much larger target. I don't think I ever ended up on the inside of a tank for more than a minute or so.
Another thing that is really frustrating about this game is that despite the fact that you appear to be quite fit in the game, you move at an alarmingly slow pace. This makes the game a bit of a bullet-hell game, but you move as if you were trudging through molasses at all times.
Co-op seems like it would be fun and it was to a certain degree but this too came with some really big downsides. It is not possible, for some reason to backtrack on the screen. You can only move upwards. The two people playing also cannot move forward unless both of them are in a position to move forward. Here comes one of the most annoying aspects of the game: Sometimes one player will get stuck behind a rock formation or something like that and since you can't move the screen back, it is impossible for him to get out. It is also impossible for the other player to move forward. The only way around this is to hope that there are enemies still on the screen that can kill the person who is stuck. If not, your game is over because there is literally no way to progress.
Another bad side of this game is that you always die in one hit. One hit from ANYTHING kills you.
The game was originally designed with a certain number of lives and had it not been for the not-so-secret cheat code of ABBA, this game likely would only be completed by some extremely dedicated nerds out there with some sort of mental disorder that allows them to memorize massive patterns.
I believe that this cheat code was intentionally leaked by the developers because they knew that their game was entirely too difficult for the number of lives that were provided so instead of fixing that, they just gave all purchasers the ability to continue to play indefinitely. This was lame as hell because now there isn't really any incentive to try to do well. You have an UNLIMITED number of lives so in single player mode anyway, there wasn't any way you could possibly lose.
When you do finally make it to the final boss and invariably kill him because you have unlimited continues, it's all bittersweet because honestly, there is no reason to ever play the game again.
Despite all of these things, the game actually sold really well and I can only attribute this to the fact that our options were pretty damn limited at that particular point in gaming history. In my mind, it was one of the worst releases a company has ever put out to market. Without the cheat code, this game would have been basically unplayable to almost all gamers.