As Mario, juggling is possible. Ridleys up-air is really good and if you find yourself in a juggling situation, Mario could be in trouble. DI (Directional Influence) is key here, you could try to bait out another up-air to then air-dodge around it, or nair and fast-fall so you can get down quick. All of these are good options, just don't get too predictable. DI-ing off-stage is usually a bad idea, because of Ridleys insane edge-guarding, more talk about under the "Recovering" tab. A possible fast-fall into Ridley then air-dodge down into the ground could possibly work. Use Mario's tools to get out of this bad situation
Mario