Griefing is an ancient practice in Minecraft that has existed since the time multiplayer was made possible. Griefing, in its most basic form, is the deliberate destruction, trolling and corruption of a Minecraft Server. Most servers do not allow griefing. Some servers, such as anarchy and faction servers, do not allow grieving.
The image shows that players intentionally grieved the spawn server of 2b2t anarchy, which is permitted due to its “no-rules” policy. This type of gameplay is popular, and many players enjoy it.
Because of its dark history, players have had the opportunity to learn how to best grieve others. It is not recommended that players grieve unless there are valid reasons.
Lava is a popular way to cause havoc on another player's base, as shown in the above image. The base can become almost impassible if it is covered with enough lava.
Another option is TNT. You can also place large amounts of TNT around the base to cause massive damage.
Players will often grief for stealing other players' or team's belongings. They will wait until the team is offline before trying to break into their base.
Also, read: 5 top features of Minecraft Education Edition players should know
Besides destruction, players in many anarchy and faction servers will create traps in an attempt to slow down their competition.
The portal trap, as seen in the above image, is a common trap. These traps are designed to trick players into entering a portal. Gamers who use this portal to teleport will be sent into an obsidian container that they can't escape from.
These servers are free from rules and players will often spawn kill to keep their competition at bay. These servers have factions that take power seriously and don't want other factions to get it.
The video below discusses the “war” on 2b2t in which the first large faction tried to stop newer players gaining power.
This video also explains “alternate profile”, a method of grieving that is offensive. Faction members will often create alternate profiles to try and join their enemy's group. This allows them to know the location of bases and can share this information with their faction.