Tried to do Noah (on Legend, even) with the team I mentioned, and nope, pretty sure this is nearly impossible with this team without 3-4 stones minimum. Couldn't even get past the second floor. Maybe I'm really terrible at combo leaders (possible, there were quite a few times when I could not figure out for the life of me how to get more than four combos from a board) or maybe this just won't work with x10.5-x12 attack and a team with low health. And maybe I just got unlucky, Valkyrie and Gabriel are still doing most of my damage with blue, and three quarters of the monsters that spawned in the first two floors were wood, so if I try again maybe the opposite will happen and I'll get mostly fire and maybe be able to do it. I guess I'll try again later, but I don't see this working, and even if it does I still only have the 40% drop chance.
Edit: Upon looking again, yeah, the green fairy is by far the worst for me. It resists me the most and is one of the two that will definitely kill me if it gets to its last attack. Had it been any of the others I definitely would have killed it, although the fact that it took me that long to do that much damage is still a very, very bad sign. Maybe if I get very lucky and get non-resist Pengdras on the first floor (and not synced, with my damage output there is a very real chance they could kill me), a non-green fairy, non-green (preferably red) Chimeras, and relatively easy legendary beasts, and my combo luck goes okay, I can probably do this. Ugh.