A few challenge levels
Inti Creates is rolling out the DLC for Azure Striker Gunvolt 2, and unfortunately, none of it involves a sequel to Mighty Gunvolt (even if Mighty No. 9 is taken out back and shot, I still want to see a follow-up with Gunvolt and Ekoro).
As for the DLC that you can buy now in Japan (it’ll likely come over at some point), you can get a new song, an extra recipe that boosts credits and experience earned, two score attack missions, and a speed run mode that disables the Electromagnetic Barrier as well as the save feature.
Unfortunately its sold piecemeal, ranging from 150 Yen (roughly $1) to 300 Yen (roughly $2) per bit. If it ever came over here I’d buy the missions for sure, but I can probably govern my own speed run, thank you.