Landmines can be used for soo many things.
But they aren’t in forge (yet)
Kill balls are
Killballs were added in the last update on tuesday. I would recommend tweeting Tom French about landmines, he tends to answer Forge related questions fairly regularly, and you can be pretty certain that your feedback is heard.
Few items persist throughout forge but the landmines have been in all of them.
Ask and you shall recieve