PlayStation Plus subscribers get Mercenary Kings as a PS4 freebie when the Kickstarted run-and-gunner scrolls onto PSN next week. Developed by Wizorb and Scott Pilgrim vs. The World studio Tribute Games, Mercenary Kings makes its Metal Slug-style action interesting by chucking in a weapon crafting system based around hundreds of different parts.

The rest of April's Plus line-up in North America features Batman: Arkham City, Stealth Inc: A Clone in the Dark, and the Castle of Illusion Starring Mickey Mouse remake on PS3. As for Vita, Velocity Ultra and Pixeljunk Monsters Ultimate HD are next month's dynamic duo.

Except for Mercenary Kings, the roster of PS Plus games in Europe is totally different: On PS3 it's Pro Evo Soccer 2014 and on Vita it's MotoGP 13, while Hotline Miami and Sly Cooper Thieves in Time are unlockable on both platforms as Cross-Buy games. That means if you get the PS3 version of Sly on Plus, for example, you'll also get access to it on Vita.

Devolver Digital recently revealed Hotline Miami is coming to the PS4 with Cross-Buy enabled, so if you're planning to get the top-down kill-fest on that platform, be sure to grab it as a Plus freebie this month. The quintet including Mercenary Kings join Europe's Plus collection on April 2. [Image: Tribute Games]