Even the most thorough historian would be hard-pressed to find any historical link between the Vikings and ninjas, but this far-fetched rivalry is perhaps the only original aspect of Ninjas vs. Vikings.
Everything else about the game, from its presentation to its gameplay, feels regurgitated.
The game's outrageous backstory does lend some light-hearted fun to a half-decent slice-'em-up, but its lack of novelty is hard to ignore.
At first glance you could have been forgiven for thinking you were playing Angry Birds. The presentation is remarkably similar, and the action of flinging ninjas into the air to knock down a structure is a unmistakably Rovio-like.
However, once you've launched one of the three ninjas at your disposal on each level, it becomes clear that the game is a slice-'em-up more akin to Fruit Ninja than Angry Birds.
The Vikings have taken the ninja princess hostage, and you have to rescue her by flinging ninjas over their towers. Tthe Vikings are naturally intent on scuppering your audacious rescue mission.
Every time you receive damage from an enemy, your trajectory is lowered, decreasing the likelihood of you clearing the tower or inflicting serious damage to the construction. You have clear the tower with one of your three ninjas or you fail the level.
In addition to this chief objective, there are three shurikens up for grabs on each stage. These are awarded according to your points total, which is increased by slicing enemies and for using as few ninjas as possible.
Vikings are defeated by slicing them with your finger, and stronger Vikings - such as those equipped with shields - need two swipes to take down. Other objects also fly through the air, including barrels and bombs.
Bombs must be swiped well away from your ninja or he'll be harmed, but you can also use them to your advantage by detonating them near multiple enemies. Friendly characters also fly through the air, and swiping or exploding them will cause your ninja to descend.
This juggling of priorities is the game’s most taxing element.
The cartoon art style, complete with comical gore effects, compliments the absurdity of this supposed ancient rivalry and adds to the fun.
But Ninjas vs. Vikings fails to offer anything significantly different despite fusing together a number of borrowed ideas. The game’s comparatively meagre campaign is too repetitive, meaning it can't compete with its rivals’ offerings.
It becomes increasingly apparent that much of the game’s appeal rests in its absurd premise.
Ninjas vs. Vikings isn’t the first game to draw inspiration from the iOS’s casual elite, but its failure to add something new to the mix means that its essential only for those who are dying to see if Norsemen or feudal Japanese assassins would win in a fight.