Games in the Mario Kart series — including the forthcoming Mario Kart 8 — are usually referred to as racing games, but we all know that's only half the story — the other half is gladiatorial combat on wheels, battles fought between competitors using whatever Super Mario-themed objects of destruction they can find in the item boxes that litter the track, and the best of these weapons is the humble Green Shell. No, really.
Green Shells travel forwards in a straight line and cause any racer they hit to spin out, and it's their simplicity that's their great strength. Everyone knows how to use them, because they do one thing and they do it well while still requiring plenty of skillful input from the player to use to their full effect. So how do they compare to the other offensive weapons commonly available to you? Shall we find out?
The Mario Kart equivalent of a heat-seeking missiles, Red Shells are a weapon for people without the talent to score a direct hit. Plus, their homing capabilities have all the intelligence of a sack of rocks, meaning Red Shells often pose more of a threat to the walls of the Mushroom Kingdom's raceways than they do to the other racers.
Even more dishonourable than Red Shells, Blue Shells aren't so much a weapon as they are a mechanism designed solely to generate spite and hatred in anyone who is hit by them. The world has plenty of spite and hatred already, thanks very much.
Bullet Bills / Chain Chomps
Aggressive, annoying and difficult to avoid, Bullet Bills and Chain Chomps are like those people who harass you with clipboards while you're out shopping, and no one likes them. If you want to play a racing game without actually having to race, maybe you should try breaking out the ol' Scalextric.
Fake Item Boxes
Treachery, plain and simple. Why not just stab your opponents in the back and be done with it?
Aside from being terribly unhygienic, having a squid shoot ink into someone's eyes is the height of rudeness. Are you really so desperate to win that you'll risk permanently blinding Princess Peach or giving Donkey Kong an eye infection? Also, it doesn't really seem to faze computer-controlled racers.
There seems to be a law hard-coded into the Mario Kart games that you are infinitely more likely to hit a banana peel you dropped on a previous lap than for someone else to hit it, making them the only weapon in the game more dangerous to you than to your competitors. A case can be made, however, for the Banana Peel's superiority to the Green Shell, but only when thrown forwards - anyone who can master this technique for stunning other racers deserves all the kudos that can be bestowed upon them.
You only ever get the Thunderbolt if you're trailing right at the back of the pack. What are you doing all the way down in last place? You're never going to get better if you have to rely on shrinking people by electrifying them to win. Hang on, that's not how electricity works, is it?
It is clear that the virtues of purity, utility and good sportsmanship are well represented by the Green Shell. That last one is especially important, because Mario Kart is a game best played with friends, but they won't stay your friends for long if you keep using Blue Shells to smash them just as they're about to cross the finish line. That path leads to harsh words, broken controllers and the occasional smack in the mouth.
No one can stay angry at you if you win using the Green Shell to fight your way to victory, because it takes finesse. If the Red Shell is Mario Kart's homing missile then the Green Shell is the sniper rifle, and who can really feel bad about taking the Nintendo equivalent of a headshot from across the map? There's little to match the satisfaction of whacking Bowser with a perfectly-executed Green Shell bank shot and then blasting past him to take the chequered flag. You can even drop them behind you, so they're like two weapons in one!
In conclusion, Green Shells are truly the best weapon in the Mario Kart series. Unless you actually want to win races, in which case yeah, it's probably the three Red Shells. Carry on!