Mighty Gunvolt, a retro-styled side-scrolling action game from Inti Creates, is being bundled in with the 3DS eShop side-scrolling action game Azure Striker Gunvolt for free until November.

Azure Striker Gunvolt, available for $14.99, comes out in North America on August 29. People who buy the game will receive a free download code to get Mighty Gunvolt, a short five-level nostalgic retro game that lets you play as Gunvolt from Azure Striker Gunvolt, Beck from Mighty No. 9, and Ekoro from the Japanese-only game GalGun. The offer is good until November 28. When you buy Azure Striker Gunvolt, a download code for Mighty Gunvolt will appear on the eShop receipt.

"Mighty Gunvolt is our little way of thanking our fans for buying Gunvolt, and supporting this kind of classic Japanese-style 2D action gaming that we don't want to see disappear," Inti Creates' President and CEO Takuya Aizu said. "We hope it'll give you a big smile - and maybe a laugh or two - to anyone who remembers the 8-bit days fondly, or even those just curious on what they missed out on back in the 'good old days.'"

Azure Striker Gunvolt is now available in Japan and is coming to North America on August 29. No word on a European release yet.