In all seriousness I use the heaviest chain I can find at Home Depot and cut 3 pieces that are about 4' each. I get an old bicycle inner tube and place the chain inside and then double over into a single 2' section, and then zip tie together. I leave a link on one end visible that I can attach a carabineer to. Most of the time 1 section will hold, but depending on conditions I might add another piece. I also have a small 2#, maybe 3# grappling anchor that I'll use.
https://www.youtube.com/watch?v=o1jAyH-1DZ4
https://www.youtube.com/watch?v=msCx3OPejLc