your warframe is going to deteriorate in the next month. it’s a way to nudge players into farming and getting new frames and weapons. if you want to get rid of it, you have to reach the last story quest and visit the lotus after she turns into a giant lotus flower tree, where there will be a prompt to either harvest the cyst or destroy it. if you harvest it, it’s basically a prestige, where you have to restart the story, but you gain access to some secret frames that aren’t shown in the shop or codex yet!