Sasquatcho's advice about slow freezing is... not wrong, but it's not the only solution to Zero's current problem. Another solution is the exact opposite of slow freezing, preferably with liquid nitrogen. Normally, water molecules form hexagonal crystals when frozen into ice, causing it to lose density and become brittle. But apparently, water that is frozen in a matter of milliseconds (either with liquid nitrogen or liquid helium) skips the crystallization and becomes what's known as amorphous ice, so a weapon made of this specific type of ice actually [i]would[/i] be surprisingly viable.

Now if only if I wrote Archer as a chemistry buff so he could realize this fact and apply it to his powers. I suppose his rapid making of ice already counts as him creating amorphous ice (meaning its already denser than normal ice) but I really wish I could come up with a technobabble way of enhancing it somehow... Hmm.