Monsters based on the book "Leviathan" by Scott Westerfield

[DoomBeast]

Fléchette Bat WIND
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Winged Beast / Effect
If you control a face-up "Leviathan", this monster gains the following effect: Once per turn: You can discard 1 card: Destroy 1 card you opponent controls.
1700/1600

Strafing Hawk WIND
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Winged Beast / Effect
If you control a face-up "Leviathan", this monster gains the following effect: If this monster attacks a monster: Destroy that monster (before damage calculations).
1800/1400

Hydrogen Sniffer WATER
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Beast / Effect
Once per turn, if a face-up "Leviathan" you control would be destroyed, it is not.
1800/1600

Message Lizard EARTH
**
Reptile / Effect
If you control a face-up "Leviathan", this monster gains the following effect: If this monster is destroyed: Add 1 monster that has "Leviathan" in it's effect from your Deck to your hand.
500/800

Leviathan WIND
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Beast / Effect
If you control a face-up monster with "Leviathan" in it's effect: Banish 2 monsters with "Leviathan" in thier effects from your Graveyard: Special Summon this monster. Once per turn: You can Special Summon 1 monster with "Leviathan"; in it's effect from your Graveyard.
2600/2100

Stormwalker EARTH
*****
Machine / Effect
If your opponent Summons a Level 3 or below monster: Banish it.
1900/1600

Dreadnaught EARTH
*****
Machine / Xyz / effect
3 Level 5 Machine-Type monsters
Once per turn: Detach 1 Xyz Material from this card: Roll a die: Destroy all monsters on the Field whose Level is equal to the number rolled.
2500/2400