15,000 knights are charging at you in full plate mail and all you're armed with is...

[T3h Merc]

1.AC-130
2.Nukes
3.???????
4.PROFIT!

 

[Crossborder]

Weed. It'll chill em out.. If not, i'll die while high- Awesome!

 

[Firesti Keralimah]

One Hammerhead Gunship (with crew), please.

Spoiler

 

[Tairan]

some sort a eletiric gun and a tank that fires water... see were im going?...

 

[OddlyThis]

Portal gun - from just inside my door to some where very very high with nothing to grab hold of. easy and I can just sit back and relax.

 

[jonnopon3000]

Lincoln's repeater from Fallout 3. Combined with my sneak skill of 75 and my small guns of 60, my various critical hit boosting perks, a single shot can kill a super mutant master.

Knights...no chance

 

[gRiM_rEaPeRsco]

I would wanna have the full weapon/armour kit of the desolators from red alert 2, turn the ground green and they all melt, lovely

EDIT: this made me lol

OR 15000 slightly BETTER knights

 

[rondler]

i would have the BFG from the original DOOM. this gun could clean a entire area in one shot, no matter where you're pointing! if this is not the best gun for this situation, i don't know what is.

 

[Jaebird]

The Citrus Bazooka, of course.

 

[Toynip]

Hate to ruin the stream of creative answers, but, why not just shoot them? Armor isn't bullet proof or even bullet resistant. Hell, arrows went through the suits.
Maybe a nice fixed gun, like a mounted 50.cal or an M60, with a rather large barrel to finish them all off.

That's why there is 15,000 of them!

Which is why I need a lot of ammo.
=]
It's not creative, but it works.

MGS3 Patriot has the solution to all your ammunition problems.

 

[Peanut Butter]

My gravity gun. I'll use them as ammo.

As much as I really, really hate saying this: /thread.

If it doesn't kill them, it'll at least distract them and make them think I'm God or something.

God or a witch!?!?

 

[Vanguard_Ex]

A SAW with plenty of ammo (if you dont know what a SAW is it stands for squad atomatic weapon)

Show off ;D

OT: If I had enough time to charge it, the Vector Cannon.

 

[happysock]

BFG, hell yeah bitches, Either that or a chainsaw,

 

[paragon1]

Atlas

 

[awesomeemosewa]

1 ODST dropping from a ship in orbit. hell all i need to do is chill.

 

[yaik7a]

An ice cream scooper and half a palatypus...they have no chance.

you ... you nijdaed me

 

[k3v1n]

pistol+no_clip+infinite_ammo= win

 

[Vlane]

The Portal Gun. You don't need anything else.

Of course you modified the gun so the portals are now ten times bigger.

 

[bitzi61]

Gonna have to go with a mechwarrior suit (Probably like an Orion, or possibly a MadCat (just cause it's classic)

Like to see how that goes, even if I don't have any ammo, I can just stomp them to death.