XCOM Declassified / Darkness II Bundle, US$5 | Borderlands 2 US$15 (Mac,Steam required)

I won't even bother trying to talk up this bargain, it's US$5! As usual, I'll provide the store description below:

Get The Bureau: XCOM Declassified and The Darkness from 2K Games for just $5.

The Bureau: XCOM Declassified
The year is 1962 and the Cold War has the nation gripped by fear. A top-secret government unit called The Bureau begins investigating a series of mysterious attacks by an enemy more powerful than communism. As agent Carter, call the shots, pull the trigger and lead your squad in a gripping third-person tactical shooter set within a covert war to protect humanity from an otherworldly enemy.

The Darkness II
Inspired by the popular comic book series produced by Top Cow Productions, Inc., The Darkness II is an intense first person shooter that delivers a twisted and gripping narrative of tragedy, modern crime drama, and supernatural horror.

Players will be taken down the brutal and personal path of Jackie Estacado, head of a New York crime family and wielder of an ancient and ruthless force of chaos and destruction known as The Darkness.

[Mac Game Store] - Borderlands 2 Complete Edition Bundle, US $14.99 (Steam Is Required)

While I don't know how long the deal is going to last, I can say it's an excellent deal if you've missed previous sales. One thing to note is the "+ all major DLC" in the description, the reason is that some of the DLC (skins for example) are not considered "major DLC". The following is the store description:

The Borderlands 2 Complete Edition includes the Game of the Year game plus all major DLC not found in the Game of the Year Edition.

In all, you get the following:

Borderlands 2: Game of the Year Edition
Borderlands 2: Captain Scarlett and her Pirate’s Booty
Borderlands 2: Creature Slaughterdome
Borderlands 2: Mechromancer Pack
Borderlands 2: Mercenary Day
Borderlands 2: Mr. Torgue’s Campaign of Carnage
Borderlands 2: Psycho Pack
Borderlands 2: Sir Hammerlock vs. the Son of Crawmerax
Borderlands 2: Sir Hammerlock's Big Game Hunt
Borderlands 2: Tiny Tina's Assault on Dragon Keep
Borderlands 2: TK Baha's Bloody Harvest
Borderlands 2: Ultimate Vault Hunter Upgrade Pack 1
Borderlands 2: Ultimate Vault Hunter Upgrade Pack 2
Borderlands 2: Wattle Gobbler
Borderlands 2: Wedding Day Massacre