The Southcore Financial Centre is a three building project located on the north side of Bremner Blvd between York and Simcoe Street. The first phase is the 26 storey PricewaterhouseCoopers Tower. This building is being followed by a 30 storey office building along with a 45 storey Delta Hotel. Here we see 18 York, PWC's address, nearing completion. Work has begun on the glass extension that will rise above the roof line.

Image by drum118

Another view. 

Image by 3rdleap

Developed by the British Columbia Investment Management Corporation (bcIMC), the building was designed by KPMB Architects. Here's what the extension is supposed to look like along with the rest of the building. 

And here's what the completed Southcore project will look like when all three buildings are complete. The Delta is on the left with 18 York on the right. 

 Additional photos can be found here.