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The Great Devourer: the Leviathan Omnibus

The tyranids are one of the greatest threats to mankind, ravenous aliens who devour all that they encounter. This omnibus contains a host of stories pitting the forces of the Imperium and the aeldari against these terrifying foes, including the novel Valedor, four novellas and more.
Warhammer 40k
omnibus

It contains:
Devourer
Shadow of the Leviathan
Deathstorm
The Word of the Silent King
The Last Days of Ector
Wraithflight
Valedor
Dread Night
Tempestus