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This guide is mainly intended to reveal an ideal location in which to complete this achievement, the rest is fairly self explanatory.

Teleport to the circled location in the screenshot below.

After landing walk left until you reach a small stretch of water with several porcupines patrolling back and forth.

Wait a while at the position in the screenshot until two porcupines are facing each other on the dry land below. At this point stomp the ground to get them to charge simultaneously toward each other.

When their heads connect you'll be awarded the achievement. You're Done.

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