I teleport a flash beam shrine (from gemcraft chapter 0) next to the wall, and sacrifice "merely" a grade 13. I could go 15, but this wall isn't worth that much...
Flash beam shrine: does damage proportional to target hp. higher grades, better percentage damage.
i use i am a soul reaper and i go full hollow and i use mah bankai on the wall and i use a grand ray cero and i kick the wall and i use FALCON PUNCH and i use LAZ0R!!!
Mega Wall One HP: 998,499 Immunites: Any number over 100 Specials: Stun Beams 100% charged... fractalman stunned. Your attacks don't count for 2 turns. Stunned: fractalman: two turns