What is the battle royales template?

[Ultra_Midnight]

With a quick search I noticed different battle royale games that seem to use the same template, they are all practically the same, can anyone help me find out which template it is?

These are just a few screenshots I have, but if you search for “fortnite” or stuff like that you’ll find more.

[colbert2677 (ThisMangaOnHiatus)]

I’m going to assume they’re using, either in part or in whole, the open source of Ruddev’s Battle Royale.