For my Mario teams advice to you, let me start off by saying it depends on how your style of play is with Mario and the person you're teaming with style of play with their character. Most of the time, I play defensive with Mario in teams. Of course Mario ain't no high tier, but he's a character who's amazing at support. This is why I choose to be defensive, especially if my teammate is the frontman and the offensive type. I can definitely play offensive and be the frontman as well, even if my teammate is a Fox. Mario teams really well with pretty much all the high tiers. Although the best teammate I recommend is Fox, then I would say Sheik, Falcon or Peach. I've been teaming with different styles of Fox players for years like Jman, Colbol, and Eggm just to name a few. Those three players I just mentioned are mostly offensive and are the frontman, although they know when to be defensive and campy when need be.
The best stages for Mario I recommend for teams are FD, Battlefield, and Dream Land. FD you can get your chaingrab on if you have those 1 on 1 moments with a fast faller and since there are no platforms in the way, Mario can excel on FD with his combos. Battlefield you can move around the platforms well and platform tech chase as well. Just make sure you're good at sweet spotting the ledge so you won't get Battlefielded lol. Mario also has one of the best magnets from his up-B. Magnet meaning you up-B to grab a ledge and its not close enough to grab but right at the peak of the up-B, it teleports to it with an instant grab. Magnet grabbing the ledge is really good on situations where someone is trying to edgeguard you with an attack thinking you're gonna sweet spot. Dream Land is pretty much like Battlefield, except bigger lol. Yoshi's Story is definitely not a good stage at all for Mario in teams. He can do good there but he can get overwhelmed at times since the stage is small and characters like Fox/Falco can be all over the place. Pokemon is good but the stage changes kinda f*ck up Mario (especially the Brokeback mountain stage lol). As you know, its a good stage for spacies as well.
On to an example of a character teammate. Lets say you're teaming with a Fox. A good team combo/assist kill is lets say your Fox teammate hit on opponent off the stage and not too far (lets say the opponent is a Fox lol). The opponent Fox isn't too far from the stage but still needs to use his up-B to recover. Always pay attention to what your teammate is doing, especially for this coming example. You're on the other side of the stage keeping the other opponent busy with your 1 on 1 fight. You notice your teammate knocked the opponent Fox off stage and is getting ready for an edgeguard opportunity. So lets say you have this situation planned beforehand with your teammate. Your teammate takes the ledge and you come running from the other side of the stage and jump off and land Mario's cape to reverse the opponent Fox's up-B. Once that was initiated, your teammate rushes quickly to the other opponent you left behind so you can return to the stage safely after getting the assist kill.
Did I mention that Mario is amazing at support lol? Not only is he good at assist killing with cape and combos, he is great at saving a teammate, especially a Fox or a Falcon. Your teammate gets hit off stage and calls for help, it should mean that he's not gonna make it back to the stage or will reach the stage but will get edgeguarded. Mario's up-B is a lifesaver as it zooms every it hits upward. It can also be a good combo breaker if you're getting comboed or your teammate is getting comboed. If you see that you're gonna reach your teammate in time to reach him/her, depending where you are on the stage, try to throw a fireball as accurately as possible to your teammate or the opponent going for the edgeguard. One example of a good fireball save is your Fox teammate got knocked off stage and won't make it back enough to reach the stage. So you guys plan the fireball save. Your teammate will do Fox's up-B at a specific angle that won't allow him/her to get closer to the stage that the opponent edgeguarding originally thinks. So you're doing the other half of the plan, which is to accurately throw your fireball so it can hit your teammate after its freefalling from the finished up-B. So you know when he gets hit with the fireball, he'll be able to up-B again to reach the stage or shine stall and then up-B.
I hope this helps you out. If you need some visual advice, you can visit my YouTube page. I have a truckload of doubles and singles videos for you to enjoy and get extra help. The playlist section has alot of singles and doubles videos in order from oldest to most recent.
Here's the link to my YouTube page: http://www.youtube.com/user/DJNintendo05
The best stages for Mario I recommend for teams are FD, Battlefield, and Dream Land. FD you can get your chaingrab on if you have those 1 on 1 moments with a fast faller and since there are no platforms in the way, Mario can excel on FD with his combos. Battlefield you can move around the platforms well and platform tech chase as well. Just make sure you're good at sweet spotting the ledge so you won't get Battlefielded lol. Mario also has one of the best magnets from his up-B. Magnet meaning you up-B to grab a ledge and its not close enough to grab but right at the peak of the up-B, it teleports to it with an instant grab. Magnet grabbing the ledge is really good on situations where someone is trying to edgeguard you with an attack thinking you're gonna sweet spot. Dream Land is pretty much like Battlefield, except bigger lol. Yoshi's Story is definitely not a good stage at all for Mario in teams. He can do good there but he can get overwhelmed at times since the stage is small and characters like Fox/Falco can be all over the place. Pokemon is good but the stage changes kinda f*ck up Mario (especially the Brokeback mountain stage lol). As you know, its a good stage for spacies as well.
On to an example of a character teammate. Lets say you're teaming with a Fox. A good team combo/assist kill is lets say your Fox teammate hit on opponent off the stage and not too far (lets say the opponent is a Fox lol). The opponent Fox isn't too far from the stage but still needs to use his up-B to recover. Always pay attention to what your teammate is doing, especially for this coming example. You're on the other side of the stage keeping the other opponent busy with your 1 on 1 fight. You notice your teammate knocked the opponent Fox off stage and is getting ready for an edgeguard opportunity. So lets say you have this situation planned beforehand with your teammate. Your teammate takes the ledge and you come running from the other side of the stage and jump off and land Mario's cape to reverse the opponent Fox's up-B. Once that was initiated, your teammate rushes quickly to the other opponent you left behind so you can return to the stage safely after getting the assist kill.
Did I mention that Mario is amazing at support lol? Not only is he good at assist killing with cape and combos, he is great at saving a teammate, especially a Fox or a Falcon. Your teammate gets hit off stage and calls for help, it should mean that he's not gonna make it back to the stage or will reach the stage but will get edgeguarded. Mario's up-B is a lifesaver as it zooms every it hits upward. It can also be a good combo breaker if you're getting comboed or your teammate is getting comboed. If you see that you're gonna reach your teammate in time to reach him/her, depending where you are on the stage, try to throw a fireball as accurately as possible to your teammate or the opponent going for the edgeguard. One example of a good fireball save is your Fox teammate got knocked off stage and won't make it back enough to reach the stage. So you guys plan the fireball save. Your teammate will do Fox's up-B at a specific angle that won't allow him/her to get closer to the stage that the opponent edgeguarding originally thinks. So you're doing the other half of the plan, which is to accurately throw your fireball so it can hit your teammate after its freefalling from the finished up-B. So you know when he gets hit with the fireball, he'll be able to up-B again to reach the stage or shine stall and then up-B.
I hope this helps you out. If you need some visual advice, you can visit my YouTube page. I have a truckload of doubles and singles videos for you to enjoy and get extra help. The playlist section has alot of singles and doubles videos in order from oldest to most recent.
Here's the link to my YouTube page: http://www.youtube.com/user/DJNintendo05