Thunderdrum

Instead of breathing fire, the Thunderdrum produces a strong, concussive sound that can kill a human at close range. The blast is so powerful that the dragon is said to "get its power from Thor himself".

Legend also has it that when the Thunderdrum hatches from its egg, it makes a sound so loud it rattles the sky. When not swelling its body up to yell, Thunderdrums can actually flatten their body by expelling all oxygen from their massive lungs for a limited period of time. In this sleeker state, Thunderdrums can better skim the ocean surface or even dive beneath the waves in search of prey. While it's true that Thunderdrums create tremendous amounts of noise, they also possess the ability to cancel out each other's sonic blasts. By modulating its roars to the proper frequency, a Thunderdrum can use its soundwaves to negate an attacking Thunderdrum's bellow, rendering it into a rather calming wave of white noise.