The 21-year-old had worked with Skepta and Drake, who said he had “so much talent” and called his death “devastating”.
Rapper Smoke Dawg, who once collaborated with Drake, has been killed in a shooting in downtown Toronto.
Canadian police said the 21-year-old, whose real name is Jahvante Smart, was killed along with Ernest Modekwe, 28, at about 8pm on Saturday.
Drake posted an Instagram story on Sunday showing them performing together.
The star wrote that such a death “is devastating” and added “so much talent and so many stories we never get to see play out”.
Canadian producer Murda On The Beat also paid tribute: “RIP My Brothers Smoke Dawg & Koba.. Love You Guys 4 Life.. Rest Easy,” he said.
British rapper Chipmunk wrote: “RIP SMOKE DAWG!!!”
Smoke Dawg was associated with the Toronto music group known as Full Circle which consists of Prime Boys and Halal Gang.
The rapper had also worked with the British grime artist Skepta on the song Overseas.