I'm not going to hold my breath on Tower of Smash, but it does sound cool, so I'm hopeful.
Intensity 9.0 Master Core is the stuff of nightmares. But with hard work and determination, I was able to beat him with Bowser. I didn't even lose a single life, though I was really close to losing one vs the clone character. I'm by no means an expert at fighting him, but I can offer some general tips for fighting him.
The Humanoid
Humanoid is the biggest target, and when he's not attacking, you can hit him from most on Final Destination. Humanoid's attacks are strong, but they're all easily telegraphed/have long start up. After you fight him enough times and learn his 'tells', you'll know exactly when to shield/block. Two of his attacks used to give me trouble, but I've learned how to avoid them now.
- The first is when he whips his arm across the stage, then a giant streak of… something flies by. The thing is that if you don't dodge at the right moment, you get hit by the tail end of the streak. The easiest way to dodge this is to either leap over the streak, or jump just before he throws his arm across. He tries to have it land directly on you, so if he does it in the air, it'll just fly over head.
- The second is the roar that doesn't do any damage, but has massive pushback. The tell for this is Humanoid making a sort of cringe/fidget with his arms close to his body, similar to when he pulls the second pair of arms out and tries to grab you with them. (I can't point out the exact difference yet. I'll need to practice more and keep a closer eye.) When you see him doing this, get close to him. The closer you are to the edge, the farther you get pushed back, and unless you have good recovery, you won't make it back.
The Chimera (Some call it Scorpion, but aside the tail, I don't see it)
This form I think actually has slightly stronger attacks than Humanoid, but aside one, all of its attacks require it being close or right next to you, to the point where it'll walk from one side of FD to the other in an attempt to get you. I've found the best way to beat Chimera is to treat it kinda like an RPG battle. You attack, then it attacks. Hit it with a smash attack or something else highly damaging, dodge its attack, rinse and repeat.
- The only attack it has with good range is when it causes spikes to sprout out of the ground beneath you. One easy way to dodge is to jump high into the air the moment you see the spikes form beneath Chimera. The spikes only rise so high, and you can whack Chimera on your way down.
The Swords
I hate this form so much, and I doubt I'm the only one. It's not that its attacks do that much damage. They just come out so ridiculously fast and cover a stupid amount of range. You'd think Master Core would be getting weaker as more of the Swarm dies, but the Swords have given me twice as much trouble as any other every time I fight MC. Anyway…
- The attack where the swords pull back and hover to the right of you before blitzing will advance to the left once it starts. Meaning, if the attack starts in the middle of FD and you run to the left edge to avoid, it will eventually catch up to you. However, it doesn't go back to the right once it starts the attack. If you can lure it to the middle of the stage, then run behind it before the attack, it will hover in place swinging at nothing, letting you freely strike at it.
- When the big sword starts charging overhead while the smaller ones try to slice across the stage, sync up with their attacks and dodge against them. If one strikes from left to right, dodge to the left, and vice-versa. The big sword falls a split second after the last little one slices. If you kept your feet on the ground the entire time, the final dodge is pretty easy.
- Though I don't see it use this attack much, the Swords will rise up then make a large slash forward/downward. If you see it rear up, just shield. This attack gives very little room to dodge due to how fast it is, and I've found it far safer to let my shield eat the attack. Be wary though – it will almost completely break your shield, so let go of the button the second the attack ends. Trust me: You do not want to be in a helpless state against the Swords.
The Clone
Because who you fight depends on who you're playing as, there's not much I can offer here. The best way to win is to exploit the weaknesses of the character while playing to his/her strengths.
- For some reason, even at Intensity 9.0, the Clone will happily fall into a fully charged up smash if you stand right beneath them as they form. They don't even dodge.
- Which is highly uncharacteristic, as the Clone loves dodging all over the field at Intensity 9.0. The biggest challenge you'll face as any character is trying to get your clone to hold still long enough for you to actually hit them. If the Clone really is just rolling across the field and doing nothing else, attempt to grab when they get close. Don't bother with pummeling though. CPUs break out of grabs really fast, so just toss the Clone immediately following the grab.
Geez, this got long. Well, I hope this can help anyone who's having trouble with him. Practice really does make prefect, so going against MC at 7.5 or so a few times to learn the ins and outs of his attacks can make a huge difference. Keep at it, and you'll get him at 9.0 eventually.