While the Greater Racket-tailed Drongo (Dicrurus paradiseus) may resemble the male Asian Koel (Eudynamys scolopaceus) with its similar black plumage and red eyes, its has two distinctive, modified outer-tail feathers that have rackets at the tip, hence its name.
This native forest bird is commonly observed in forested areas throughout Singapore. 
It is a proficient imitator of the calls made by other birds.

Singapore Botanic Gardens, Singapore, 7 November 2022