step1repeat: execute @e[type=lightning_bolt] ~ ~ ~ fill ~-3 ~ ~-3 ~3 ~ ~3 summon creeper
step2 chain#1: execute @e[type=xp_orb] ~ ~ ~ summon tnt
step3 chain#2: execute @e[type=tnt] ~ ~ ~ fill ~ ~ ~ ~ ~3 ~ stone
step4 chain#3: execute @e[type=creeper] ~ ~ ~ summon xp_orb
step5 chain#4: execute @e[name=shield] ~ ~ ~ fill ~-10 ~-5 ~-10 ~10 ~10 ~10 air 0 replace stone
______________________________________________________________________________________________________________________________________________________________place a armor stand called shield in the middle