well I thought about having him turn his arms into stone for an attack and maybe some stone mask headbutt
It would look like he is protecting himself from harm though, which I think is not required to display how powerful he is even without special abilities.
petrification hex edit? what is that?
Today I would side with Trickity and prefer a character/feature that does not require such a huge edit to the whole game.
haha tell me what you had in mind yinyin?
I think he should be a force tied to the ground. And his game play needs to reflect that.
To manage that he should have a low jump and dash (like Mark). And since he looks rather buff most of his ground frames (maybe even attacks) could use the defense state 7, while he will always be fully vulnerable in the air. Also the two aerial attacks he has could be made rather risky/weak compared to his ground attacks. This could be achieved by making him recover slowly when landing after an aerial attack and by giving all his ground attacks the ability to instantly break defenses, while the aerial ones have no backup force to manage that.
(C+)
D>A (+A+...) Rock Shackles (default blasts, temporary immobilization)
Blasts thrown in a similar motion as Firens D>A, except flying lower and slower (and either only two in a row or unlimited like Julians D>A - one attack button per projectile though).
Upon contact they would form rock around the feet of the opponent, holding him in one of the broken defense frames (using the others as back and fronthurtact). To make this match up with larger characters like Knight and Julian it would hold all of them a 100px high and cover the bottom 20-30px (feet of normal characters, legs of Julian/Knight). Like ice this would release the opponent after some time. Unlike ice you can hit him with a weak attack twice before he will break free. Since a second blast would have to break an immobilized opponent free, I would either have him throw these at an angle (like Woodys D>A) or further to his sides (on z axis, right and left). That way they won't interfere too soon and shorten the time of immobilization.
Additionally this could be performed once upon a caught opponent, fully or partially (up to the neck) covering him in stone. That would be a heavy object catching the opponent out of Magnus' grip. You would be able to carry around the imprisoned opponent (but not harm him). Damage will be dealt to the opponent upon breaking the rock and setting him free. The object itself can deal heavy damage to other opponents, but should probably break after the first throw. (This whole thing might not work if the z movement of the cpoint does not follow when carrying the weapon.)
(J+)
DvA (+D^J) Earthquake (large area of effect, crowd control, stun move)
He performs a very small hop and forcefully lands with both feet (or drop directly from a jump/dash).
This would cover an area similar to Henrys flute, visible through a grey scale crack outline animation on the ground. It would however be just a single short hit, stunning multiple opponents (or breaking their defense). It can easily be dodged by jumping (itr would only have a height of 1px above the ground).
(DvA+)
D^J Rock Walls (semi large area of effect, defensive/protective)
Crossing his arms in front of his chest and swinging them down, out and up; creating two arched rock walls to his sides (possibly made up of several objects). They will block characters like icicles, but absorb more hits. If performed directly after an earthquake, more walls will appear.
D>J Rock Prison (grapple move, unlimited opponent confinement)
A grapple move like Louis' D^J, which will directly perform the earlier mentioned C+D^A (since it is a pretty rich feature on its own, if it works).
If it doesn't work he should definitely have a non energy powered move, like Woodys flip kick or Julians uppercut. Actually even if it does work he could certainly have an additional semi special move like that.
