Nightcrawler: Play in the Dimensional Rage
When in training mode as Nightcrawler, turn on "Infinite Specials" then perform the Dimensional Rage technique. You will be in the Dimension for the technique. Perform a different special other than Dimensional Rage and make it contact. This will cancel Dimensional Rage and leave you in the darkness. To exit, perform the Dimensional Rage again and let it finish properly.