Why the Coolest Weapon? In a Zombie Invasion I would want the most damaging thing possible. I've seen some cool things but that doesnt mean they are strong.
I'd have to agree with d_dude on the choice of weapon, though what you meant were not pikes but halberds. Halberds keep the enemy at distance and has some advantages compared to spears or pikes.
Pole weapons in general are cool weapons, there are various types and many types have multitudes of cool designs.
I would want a lightsaber, or a machete. In a zombie invasion, blades are better then guns because; Guns are noisy,guns can jam, and the most important of all...
A melee weapon (from French, mixed, referring to groups of fighters interlocked in close combat) is any weapon that does not involve a projectile â" that is, both the user and target of the weapon are in contact with it simultaneously in normal use