A cult saying first made popular by MMORPG players in anticipation of the game Mortal Online, it was first said by Kudo Sinoda during the Xbox 360 project Natal demonstration for E3 2009.
During the demonstration the motion sensors responded horribly sending the on screen avatar into some kind of epileptic fit.

The term was first made popular in Mortal Online IRC channels, where Sampzky and other Mortal Online Beta applicants watched the live E3 2009 press conference together in the IRC channel.
Today, the term 'WAH BAM!' is used to express total failure; failure which is usually executed in a retarded or spasticated fashion.

The full quote is as follows:

Kudo: "You ever wonder what the bottom of an avatar's shoe looks like? WAH BAM!"

*Onscreen avatar cripples and flails horribly*

Kudo: "There it is...?"
Player 1: Hey, lads! Watch me solo this boss mob!
....
Player 1: I forgot my armour and weapons and FarmerJoe killed me :(
....
Player 2: WAH BAM!!!!
by Sampzky June 2, 2009
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Something to yell when flipping it off to someone.
When i saw him round the corner i looked at him, and flipped him while saying, WAH BAM!
by PaineXNoctis December 4, 2014
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