The Stones System
Currently in 3 flavours
Rubies! This is something you should do every day, even if you can't get the highest rank! Two minutes of play for rubies can't be argued with! If you follow the strategies, you'll get relatively LOTS of rubies!
Most videos will show fast times but not explain what is going on. The key thing is that supers pause the clock, and used with certain strikers, will wipe out two waves of minions with one strike. Novice is actually the hardest because you don't get to choose your setup, or add cards and stones. Master and Veteran are much easier, with the latter simply relying on strength more than anything else.
You'll need some luck and a character combination that can build meter and wipe out enemies quickly. Best leaders are Yuri 98 for power gauge, any character that gives you a 50% or more boost such as Shermie 97, Ryo 96, Haohmaru, Hinako etc. Choose a striker that will buff you such as Festival Billy Kane, Thug Cena, Robert 97, Vanessa etc - check for special relationship extra buffs. Characters like Zero give a passive buff to Lady Zero- it's active all the time, not just when summoned.
Remember that these characters at Novice Level are level 70 and so they are underpowered.
There isn't a guaranteed universal strategy, you do need some luck for minions to fall into place.
The first group of attackers will land in front, the next will be behind. You’ll need a fighter that has a wide range attack. Position yourself at the top left of the screen so that the enemies will line up in front of you. When you move forward, position yourself at the right side so that you can use one move to eliminate many opponents, don’t waste time fighting one and then turning around to get the others. Save your ultimate attack (3 power gauge only) for the mid boss. Do not tag out as you will need to build power gauge again. As soon as Athena appears, use your full screen ultimate attack. On the next screen move to top left again. Defeat the group of attackers with one special move. Now run forward to the right side, and line up the two goons so that when the large samurai ghost appears you can wipe them all out. When the boss appears, call your striker, do your super move, tag and repeat. Save all your ultimate attacks, as soon as you build enough for a super (3 gauge moves are best of course), tag out. Then you can unleash on the boss. Another way is this Orochi Iori.... pay attention to how the player uses the supers to pause the clock, using O.Leona with the striker tech to wipe out 2 waves (Just tap striker then do your super). Pretty Zero is another character that can do it at this speed.