You can check out the three bundle options using this link.

Dust off your side-scrolling skills and dive into some of the best 2D games ever created with this massive collection of Mega Man games! A substantial chunk of the Blue Bomber’s storied history is at your fingertips, starting with Mega Man Legacy Collection 1 and 2, which compiles all the mainline titles. You’ll also get Legacy Collections for the Mega Man X and Mega Man Zero and ZX series, plus the standalone Mega Man 11. It adds up to a total of 25 games across 36 years of Mega Man! Pay what you want for this bundle of essential gaming, and help support JDRF with your purchase.

You can always check out the most recent Humble Bundle offers here and here.