The Bouncing Barrel is a hazard that was first seen in the original Crash Bandicoot game. They are normally thrown by enemies intended to harm Crash. They generally appear as relatively small and brown, with a toxic warning sign painted on.
In the first game, the bouncing barrels appeared solely in the level Toxic Waste, accompanying the rolling barrels. They appeared later on in the level near the end, thrown by enemies down pathways and slanted paths. They could be dodged by passing underneath, jumping above, or jumping around.
Whilst avoiding them when bouncing on the regular paths was simple enough (yet notably more difficult than dodging the rolling barrels), dodging them when on the slanted pathways was notably difficult and one of the biggest challenges on the game, requiring pretty much perfect timing.
They first appear with the penultimate enemy, who threw one bouncing barrel after every two rolling barrels. At this point, it was easy enough to avoid continuing up the hill after waiting for the bouncing barrel to pass. However, the final enemy throws just bouncing barrels, making things more difficult.
The Bouncing Barrels appeared in Crash Twinsanity as well, not being seen as a hazard in levels since the original. They appear on the level High Seas Hi-Jinks, thrown by N. Gin's animal minions on his battleship. This time, they are not thrown straight forward, but appear thrown down a sideways hill, before hitting a wall and bouncing down a different hill in the opposite direction. They are larger now, but bounce slower and it is possible to jump up to the second hill pretty easily, making them easier to deal with than they used to be.