HP Threshold for Surviving Trinity's Board Blast?

Just got into re-playing this game...
To gather up the story elements & NPC info & etc. Because each 'run' is a little bit different depending on which character type you pick (HU NE CA) I am on a Newman run now, but ran into trouble with Mother Trinity. Thought it would be fine since Humilias was NP.

Does anyone know what the HP threshold for survival of her "Board Blast", where she hits the whole chess board with a big energy blast? I've looked at the guides, all it talks about is what her "chess pieces" do, how 1 is HU, one is RA, 1 is FO, etc, but they don't say HP limit for living through that big hit, or have a way to make her to not do it.

It's higher than Humilias (Which, everyone had issues with because he "double shots", if the bullet of his gun hits you, it SE's then he rushes in with the blade to strike) My guy lives through that just fine, so I THOUGHT it would be ok to face MT (I'm just going for plot, this is on normal mode, I'm not making this guy to raise/keep/level go into other modes)

If the HP threshold is too high, how do I level more without dropping the quest and having the play the whole 2nd half of the game again?

(You are rail-roaded after doing "A far journey" without ever being able to go back to town, into beating the game/Trinity. I don't want to have to do it all again just because I dropped the quest to take another to level the guy more)

I was always Cast on this game previously, so that was probably why the character always lived.

Any hints are appreciated for plot-related documentary purposes!

I don't think its possible to survive the move where MT "pings" for a bit and then drops down her arm causing a dark eruptionaround her Pieces. You can avoid it by standing far away from her Pieces, but you wwon't be eating that damage anytime soon, or at least you should be seriously considering avoiding it and not trying to just tank it like a plank.

Also, your progress of the final three areas in Story Mode is tracked and maintained after you save during the process. Once you get to the Dark Shrine sehment, for example, you will be able to cancel the main quest, and come back to it at any time by the new quest name of "Curtain Call", which starts you back off at the beginning of the Dark Shrine.

Is that the attack where a bell rings then after 3-5 secs lazors decend on the arena? You can avoid it by moving around without getting staggered or dodge roll. Sorry I am not familiar with the attack your talking about. =<

For the photon eraser (when you have a target under you) ,just jeep running around. For the pieces explosion you have to stay afar and wait. Little trick : If you use a photon blast after beating her (during her "falls" ) , you'll be invincible during the battle vs dark falz