I remember playing this game when i found it downloaded. Took me a while to pass the boss entirely as I found it difficult due to how wonky this game is. Its not a bad game I'll say that, however there's issues I know that can be fixed up, though this IS an old game I played back then and it wasn't as difficult as I remembered.
Hit boxes on the shots and enemies are weird, especially enemies aren't destroyed as soon as they enter the screen, more notably the Helicopters and Triangular Ships that sway and shot 3 shot red bolts. The power ups don't make much of a difference as they're pretty much also wonky on hit boxes but I guess its cool to see your shots turn like a massive 32 gun gold bolts.
The controls are okay, smooth, and responsive at times, the 1st boss I have trouble avoiding the Yellow shots as sometimes my ship would freeze or stay still as I got killed suddenly.
Enemies are standard and that's it, only thing is just their hit boxes and how they shoot a little. A bit weird but standard.
The Bosses are also standard, multiple ways to shoot before they get close to destroy you and repeat, the good thing is the power ups continuing to spawn so you can literally farm lives if ya want. Easy to dodge at times minus my ship freezing at moments where it would kill me which got frustrating. 2nd Bosses and beyond are actually easy if you got the 2nd power up and above.
Overall, this game isn't too hard, not really the best way I can see this game being played well but its not bad. Could definitely use improvements, graphics are actually pretty good hence why I also like this game. Acid and Speilberg are the same, just different music. Its kinda fun playing with WW2 music in the background, kinda gives more of a feel to it in my opinion.