Besides what depleted said, the blood in question is the result of a magic curse, as far we know its not physical at all, and we are explicitly told that warp stuff cant sustain tyranids
biomass means mass of organic matter, blood is just a liquid for the transport of oxygen and some trace elements.
tl;dr: wouldn't work, they need corpses, and everything else.
Tyranids use far too much biomass for this to be anything beyond a Grimdank idea. Not to mention the blood is most likely warp stuff turned to physical form and wouldn't nourish tyranids in the first place. It would either burn or poison them most likely. This isn't a good idea. Bold to assume also that an Avatar of Khaine wouldn't go down swinging or have a warp-esque explosion of bits of metal and burning blood..
Besides what depleted said, the blood in question is the result of a magic curse, as far we know its not physical at all, and we are explicitly told that warp stuff cant sustain tyranids
biomass means mass of organic matter, blood is just a liquid for the transport of oxygen and some trace elements. tl;dr: wouldn't work, they need corpses, and everything else.
Its nowhere near enough blood to feed all of them, and why would the tyranids do that, to my knowledge the hivemind enjoys killing others
Tyranids use far too much biomass for this to be anything beyond a Grimdank idea. Not to mention the blood is most likely warp stuff turned to physical form and wouldn't nourish tyranids in the first place. It would either burn or poison them most likely. This isn't a good idea. Bold to assume also that an Avatar of Khaine wouldn't go down swinging or have a warp-esque explosion of bits of metal and burning blood..