Looks like the Humble Store has set up a discount for the Destiny 2 - Expansion Pass for $19.99(43%). However, if you have the Humble Monthly subscription, it gets further discounted to $17.99(49%).
Requires Destiny 2 on PC to play. Requires a Battle.Net account to play.
This deal expires on June 15th, at 12:00 PM CDT [timeanddate.com]