The movie
Meet the Spartans (Sean Maguire, 2008) uses paintball guns in one scene of its parody of the film
300.
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In a scene parodying one from the movie
300 (2006) King Leonidas (Sean Maguire) beats on his son, Leo, Jr. (Hunter Clary) with a clay pot,
a folding chair and a chainsaw, until finally he brings out a Kingman Spyder Xtra paintball gun and uses it instead.
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Leo, Jr. takes several hits (although they appear to be low-velocity blobs of paint with no shell.)
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The Captain (Kevin Sorbo) and Queen Margo (Carmen Electra) then join in.
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They pause for a moment, as the Captain notes the Persian Emmisaries
are waiting. The Captain is holding a Tippmann Model 98 with a
7-ounce
CO2 tank on an unknown drop-forward, an Armson Pro-Dot sight and a
Viewloader 9V Revolution loader. Queen Margo has another Spyder Xtra.
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Just before leaving to meet the Emmisaries, Leonidas fires one last shot.
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Which strikes Junior square on the forehead, knocking him out.