Eclipse credits are an in-game currency in Marvel’s Midnight Suns, used to buy high-end cosmetic skins for characters through the games marketplace. The Eclipse Credits are quite different than the Gloss, which is another currency in Marvel’s Midnight Suns exclusively dedicated to cosmetic upgrades. Eclipse Credits are used to buy higher-quality costumes, unlocks for special versions, and ones found in the Marketplace.

Eclipse credits are a premium currency in Marvel’s Midnight Suns, and will require cash purchases. It is understandable that players are still frustrated about not getting any new cards included in the game, but know that the 300 Eclipse Credits and a lot of full-costume cosmetics are completely optional, only acting to improve the aesthetic experience. Their unique battle attires can appear on the Marketplace, which allows you to purchase them using Eclipse Credits.
These are particularly helpful in getting needed resources for upgrading maps, installing new upgrades to Abbey, and getting hero cosmetics. However, the act of unlocking the cosmetics can take some playtime, and also some money. The Hunter player character has a few unique battlesuits, which are unlocked through certain requirements.
The Hunter, the player-created character, is the only character where outfits can be unlocked by just playing through Midnight Suns. Beyond this, there’ll be markets throughout the game housing the skins of the game’s other characters. Characters also have Midnight Sun variations, which are acquired by only clearing the relevant Midnight Sun Challenges within Armory.

You definitely want to be playing with all of Marvel’s character creation and customization options for Midnight Suns during your time with the game. Other people’s tolerances may differ, but at this point, I would recommend against this experience, even though it works.
Once you have played through Marvel’s Midnight Suns enough to get access to Forge and Exploration, be sure to get your War Games project started ASAP so that you can buy the Foundry upgrade, which greatly enhances the analysis for Gamma Coil. Players will still need to find the new cards by playing Marvel’s Midnight Suns and using Gamma Coils, rather than through some sort of buyable loot box. Once you have completed your wargame projects by the next in-game day, you can purchase a Foundry Upgrade: this costs 50 credits for instant installation, so keep those credits handy as well.
These skins are available for purchase using Eclipse Credits, which are acquired exclusively through the use of real-world currency. Redraws are good to rid yourself of unwanted cards, but you should use them for a few of your best ones as well.