Classic Sierra games are in the spotlight once again -- in benefit of the Call of Duty Endowment, Humble Bundle and Sierra are offering deep discounts for both classic and newer PC titles. Notable titles among the group include Geometry Wars 3: Dimensions Evolved, King's Quest, TimeShift, and Velocity 2X.

For only $1 players are able to pick up Space Quest Collection, Phantasmagoria 1-2, Police Quest Collection, Shiftlings and 10% off Humble Monthly for new subscribers.

At the next tier, for $9.71 (at the time of writing) players can grab all the previous games, as well as Arcanum: Of Steamworks and Magick Obscura, TimeShift, Quest for Glory 1-5, and Gabriel Knights 1-3.

Meanwhile, at the $15 tier, players are able to get all the previous perks and Caesar 3-4, Geometry Wars 3: Dimensions Evolved, King's Quest Collection, and Velocity 2X.

Finally, at the $20 tier, players can unlock King's Quest: The Complete Edition  -- including all five chapters and the epilogue.

The bundle is available for the next six days, so make sure to check out the deal here.