Want to truly infuriate your buddy? Get ready, ‘cause this one’s a doozy.
I recommend starting this in a flat land, and be aware…this is going to take a WHILE. If you wish to search for a seed that will do the job, that’s fine too, but good luck finding one. I’m not sure it would even exist. Start a flat land and just take out all the dirt. Just erase everything and replace the entire world (or at least an enormous portion of it) with water, so basically it’s now one gigantic ocean. Now, build a little island for you and your buddy to stay on. Nothing too fancy, but give yourself a nice home and some beds and food and tools. You know, enough to not make them suspicious, ‘cause let’s be honest, you’ve been kind of a dick so far through these. No need to make them any MORE suspicious than they already are.
Once you’ve done this, go build another island a good while away and REMEMBER WHERE YOU PUT IT IN REFERENCE TO YOUR HOME ISLAND. I can’t even STRESS how important that is. Build a little island and a small cave with a mine, inside of which you will just place a plethora of materials, such as diamond, gold, iron. Just blocks of each ore upon blocks of each ore. Once you’ve made–what appears to be–the greatest find in Minecraft ore history, go and create 5 separate islands. Now comes the fun part.
At each one of these islands, build yet another small cave and mine with more ore. Oh, and also, spawn a different enemy in each. In one, spawn an infinite number of Creepers; another spawn an infinite number of Endermen; Skeletons on another and so on and so forth. Now…invite your buddy.
Now hopefully they will start near your home island, which may be the only thing that can ruin this.
Once they’re there, tell them downloaded someone’s seed and that you found just caves full of ore. Give your friend a boat and make them follow you in your own boat to the GOOD island. Once there, spend enough time mining and chatting to make them feel comfortable. After you do this for a bit–not too long, 15 minutes or so is fine–tell them you’re going to take your ore back to the home island, but there’s another couple islands filled with ore too and that they should go check those out. They will get in their boat and start exploring, and come across one island after another, each promising massive amounts of great ore but instead delivering them to pure terror. The great thing is, they’ll find the one full of Creepers or whatever they find first and think “Hey, that can’t happen twice, right?” because what’re the odds, seriously? They’ll soon find out that they were dead wrong.
Not only will they become increasing infuriated by the fact that there’s groups of mobs everywhere, but they also won’t really suspect you because who honestly would go through all this trouble just to grief?
You would, you jerk, you.
But you think it’s over? You think they’ve suffered enough? Sir, you are mistaken, as we have one more trick up our sleeve. After a few islands of terror (Islands of Terror, now at Blockbuster in the $3.99 bargain bin!) you will also create one final island, which you will invite yourself along to. This is to give them the false illusion of security and safety. Lull them into this one easily. In this final island, you will make–again–just a cave full of ore. However, under this cave, you will have mined the floor out and replaced it with TNT, upon which you will break a piece out once you’re in. Finally, take out a flint and steel, ignite that sucker AND RUN LIKE HELL.
Griefing: America’s new past time.