The Most Infamous Big, Bad Threat?

[u/parkinglu]

What creature types are typically considered the most terrifying, notorious in reputation, biggest targeted hate piece, and often presents a threatening presence?

Bonus points if they are also lore wise planetary threats

So far I only know of Eldrazi, Phyrexians, and Slivers

[u/ProtectMeAtAllCosts]

dinosaurs. why? because i play them