I think at this stage I would prefer something more concrete like a shit ton of snipers all shooting at him simultaneously so we can count on at least one round to do it's job 👍
Im no expert in bullets, but maybe something large calibre and could explode/fragment so would make a nasty mess of what passes for human flesh be in order and do the world a favour 😉
lol....feed him up with big macs stuffed with meat from the heart attack grill first, he prolly wouldn't make it a couple feet before his heart gives out XD