A while ago, I came across a cool thing. You can summon tnt that never actually goes off. After figuring this out, I thought, hey, what if I could make it follow the player? So thats what I did. Summon a tnt pet by throwing a totem of undying on the ground with a block of tnt. Your tnt pet will appear at your feet! You tnt pet will follow you, and attack mobs. You can summon as many as you want. Have fun!