Pentagon

Pentagons are blue passive shapes with five sides. They have 20 health and give between 100 and 300 experience. There are numerous variants of pentagons, all much stronger. The Pentagon Sanctuary protects pentagons and spawns a Leviathan when killed.

History
The Pentagon is present in Diep.io, Arras.io and Woomy Arras.io. It is an original shape. Beta Pentagons are present in Arras.io.

Green Pentagons were added on 28 May 2018. On 16 September 2018, Green Beta Pentagons were added. It is unknown when Burnt Pentagons were added. It is rumored that Burnt Beta Pentagons exist, but this is unconfirmed.

Pentamancers were added on 7 September 2019, and are able to infect any type of pentagon, including Burnt, Beta, and even Alpha Pentagons.

Green Pentagon
Green Pentagons are stronger than normal pentagons and give a poison effect when touched. They give 5,000 experience when destroyed. It can spawn 0.4% of the time instead of a Pentagon.

Burnt Pentagon
Burnt Pentagons are very rare, spawning only 0.4% of the time from a Green Pentagon, making its relative chance 0.0016%. They give about 13,000 experience, but take a lot of time to destroy.

Beta Pentagon
Beta Pentagons are stronger than the regular Pentagon but weaker than a Green Pentagon. They give 3000 experience when destroyed, similar to Diep.io's Alpha Pentagon.

Green Beta Pentagon
Green Beta Pentagons have a 1 in 175 chance of spawning over a Beta Pentagon. They have been observed only a few times.

Burnt Beta Pentagon
Burnt Beta Pentagons are an unconfirmed feature that have been reported to exist by a few users. However, the changelogs do not mention such entities. If they do exist, they are likely far stronger than an Alpha Pentagon.

Sanctuary
The Pentagon sanctuary is a five-sided entity that spawns many giant pentagons and generates a nest around it. The nest can include Green Pentagons, Sentries, and Crushers. When destroyed, a Leviathan will spawn to avenge it. The Pentagon Sanctuary is the rarest regular sanctuary.