Assuming the "Civilian" Thunder_Alert went into the portal on his own, unfortunately, it is his own fault. Also, he can warp back to the place's spawn with /Warp or escape by doing /is.
You cannot type will in a portal There is a lack of evidence since we cannot see monster trapping him.
This isn't a lack of proof. All @HGcrafter has to do is get proof that this is Monster's Island then it will be good enough. @daelwolf @Dovashy
To do this, @HGcrafter , just take a screenshot when you come into his island and the chat says "Entering a protected island area (Monster79928)"
I know, but if he goes there again and he gets a pic of when it says "Entering a protected island area (Monster79928)" then it is good proof
There is proper evidence that it is Monsters island and that he did it. Staff would have to decide whether it's a temp-ban or perm-ban. Also I was talking to @VolgaDecimo when I said this. I wasn't refering to anyone else. So you didn't have to answer.