A virus isn't really "alive" in the technical sense, but there are engineered strains of this and that which could kill billions if they were turned loose. And which creature stands behind them? Man.
Hippopotamus.
A lion seal I think!
Man is probably to answer to both.
Because it is so well armed!! Lol!
Giraffe
a tiger
A crocodile
Dart Frog
possibly plankton
The human baby.
The most poisonous creature is the sea snake.
they r the most adorable creature on earth!!!!!!!!!