Sauroposeidon
The press release in 1999 immediately garnered international media attention, which led to many (inaccurate) news reports of "the largest dinosaur ever!". While "Sauroposeidon" likely represents the tallest known dinosaur taxon, it does not hold records for either the longest or most massive. "Patagotitan" or "Argentinosaurus" make better candidates for the title "World's Largest Dinosaur" (presuming to ignore, as is conventional, "Amphicoelias"), though incomplete fossil evidence makes exact rankings impossible.
Dakotaraptor
"Dakotaraptor" was about long, which makes it one of the largest dromaeosaurids known. It had long arms with one of the lower arm bones showing quill knobs, demonstrating that it was most likely feathered. It also had long rear legs with a very large sickle claw on the second toe; this claw could be used to kill relatively large plant-eating dinosaurs. It lived in the same time and area as many iconic late Cretaceous dinosaurs such as "Ankylosaurus", "Triceratops", and "Tyrannosaurus".