How Tibia's open-PvP made it one of the most interesting social experiences in the MMORPG genre.
Tibia is a pretty wild game. Released in 1997, it started as a college Project made by a group of friends. The game eventually grew to become very popular, with hundreds of thousands of active players, and it's arguably the oldest MMO that still has a large playerbase. It still gathers about as many daily players as it did in 2007, during its peak. However, the majority seems to be playing one of the hundreds of active private servers, which aim to capture the gameplay of the earlier versions.
The game is definitely very different nowadays. For many people, it lost the aspects that made it more unique, in order to try to "modernize" itself and become more similar to what other MMORPGs are. When Tibia was released, the MMO genre wasn't even well-defined, and thus many of modern conventions didn't apply. Anyone who looks at how the game played in its early days will notice that the design philosophy is that of something that just would not be released in the modern times. I will be focusing in Tibia's early 2000s days, what people consider to be the "golden era" of the game.
The one thing Tibia was known for was its harsh death penalties. Not only you lost a BIG chunk of your total experience upon death (potentially resulting in the loss of many levels), you also dropped your entire inventory, with the chance of losing some equipped items as well. The experience penalty was bad enough, but the item drop turned every player into a target for other players.
You see, in Tibia, you could be attacked and killed ANYWHERE, with only a few exceptions, the "protection zones" such as temples and banks. People would constantly go to leveling spots and try to kill players for all the loot that they had been gathering. And you always had to be wary of signs that someone was going to try to kill you. While there were restrictions and penalties for someone killing indiscriminately, they typically only applied if there was another capable of killing them to begin with. If you were strong enough, people were at your mercy.
The first reason why it made for a good social experience is that this design philosophy inherently encouraged people to try to not be "loners". Having friends who could come to your aid in case you were being attacked was a blessing. Simply having high level friends was enough to fend off potential attackers. Maybe normally they'd try to kill you for your loot, or just attack you to chase you out of a good leveling spot, but players would think twice if they thought you had someone stronger on your back. Joining a guild was a big deal for this exact reason. People would know instantly that you were not a "loner", and would be way more scared of messing with you.
The second reason builds on the first: guilds weren't just about defending from being abused. They were often the abusers. It was one thing to be in a guild of nobodies. Being on a notable guild, however, was a different story. If your guild was known for having many strong players, you were emboldened to have others at your mercy. If you wanted, you could close off a good leveling spot and tell other players to leave. The intimidating aspect of being in a strong guild was enough for them to obey. You could kill others freely as people would be afraid to help or retaliate against someone backed by a powerful elite. In this sense, the game played like a big mafia.
Like said previously, being killed in this game was something every player was afraid of, but there was something worse that could happen to you. You could be marked as "hunted" by a group of players. This basically meant they would constantly be trying to kill you. The game's mechanics allowed for players to known when another is online, as well as knowing their location. You could not hide from people who wanted you dead. And due to the harsh death penalties, you could effectively be on a state where the game was simply not playable for you anymore. Either you had to create another character or try to negotiate a truce with the people trying to kill you (usually it meant paying a large sum of gold).
Marking a player as "hunted" wasn't generally something people would do on a whim. It was a punishment for infamous players or just someone who messed with the wrong people. However, there were guilds that gathered negative fame for being cruel towards anyone they wanted. If a dominating player could have anyone in the server at their mercy, a dominating guild could have the entire server at their mercy. Often were the cases where this happened, with the strongest guild around dictated the rules. Even strong players had to follow them, or else they effectively faced the prospect of losing their ability to play with their character.
Alas, but no bad deed goes unpunished, and even the most powerful tyrants could be toppled down. Powerful groups could enter conflicts for a myriad reasons. Because of personal conflicts between their players. Because people were tired of powerful, tyrannous guilds, or even because each one was fighting over the status of being the dominating guild of the server. These were called the "guild wars", where their players would be constantly trying to kill each other. This would often result in large-scale battles that could occur anywhere in the map. They marked dark times in a server, where you could never be sure about which place would become the next battlefield. Players in a server would constantly talk about what was happening. Some would be hoping that a guild's reign of terror over a server would end. Some wars involving particularly famous guilds and players would become so notable that entire forums would constantly be talking about it, posting videos of large battles, and so on.
The hows and the whys for these guild wars were very varied. Sometimes it just happened that many smaller guilds, as well as "hunted" players would group-up in order to try to take down a dominating guild, using guerrilla tactics to wear them down. Sometimes the strongest players of the game could single-handedly tip the scales of the wars, and their occasional deaths would make the news over the whole game. People would create characters in another server to try to accompany wars involving famous players. The stakes were high, and the results changed how a server would work. The winning side could simply kick off the losers from the server. Or maybe they'd be nicer and bring an era of peace. Sometimes the "good guys" could become the next tyrants.
Tibia's lack of restrictions is not something you see often in modern games. The ability to interact with other players in destructive ways turned the game into an unique social experience. How often do you see a game where the most famous players are ones who are particularly strong and influential in-game, rather than streamers and e-celebs? How often does a player become so infamous in a community that others group up to try to hunt them down? How often do servers end up having different hierarchies and rules dictated and enforced by a notable group of players?
Nowadays, people have less reason to play punishing games where they have the possibility of losing their hard work on a character because others want to. They will just play fortnite instead. Sadly, this means that the sense of community in MMOs died off, with more and more games basically becoming solo experiences where players are not encouraged to group up or make friends. This is an art in gaming that is hard to replicate in modern times.