Charlie Ninja/YMMV


 * Fridge Logic - Sometimes spikes are hidden into boxes and barrels instead of bonuses: if you step on them, you will lose energy, but then enemies who step on them also get hurt, stopping for a while and rendering them easier to kill. However, spikes are the only trap in the game that can hurt them... they are immune to everything included flamethrowers and land mines! (The player, obviously, is not).
 * I Am Not Shazam - No ninja in this game is named Charlie, their names are Roy and Lon. According to the end credits, Charlie is the nickname of the game's art director/character designer.
 * Older Than They Think - The second stage looks like a homage to (or parody of) Metal Slug, what with all the crazed soldiers, tiny tanks and trenches... However, Charlie Ninja was published more than a year before Metal Slug.