Ancient Rex SW145SD

Ancient Rex SW145SD is a 'evolved' version of Nightmare rex and belongs to Agito.

Facebolt: Rex
Same as Nightmare Rex. It features a Tyrannosaurus Rex, one of the most well known dinosaurs.

Energy Ring: Rex
It is the same as the original Rex clear wheel, except that it is coloured black.

Fusion Wheel: Ancient
Probably the same as Nightmare, instead it is coloured gold.

Spin Track: SW145
Switch 145. Same as Nightmare Rex.

Performance Tip: SD
Stands for Semi-Defense. Same as original Nightmare Rex.

Trivia

 * Strangely and coincidentally, there is a character in an anime show called Dinosaur King called Rex Ancient. Ancient Rex is just his name backwards, it is most likely coincidental.