The Green Pentagon is the rarest confirmed Polygon in Diep.io, and the second strongest in regards to health; the strongest being the Alpha Pentagon. The Green Pentagon grants a total of 13,000 EXP when destroyed. There have been very few confirmed sightings of it, but it allegedly has ten times the health of a regular Pentagon.
It is by FAR the most EXP-giving Polygon in the game. A player killing it at Level 1 will directly rise to Level 37. In Domination, Tag, or Survival, killing this Polygon can allow the player to rise to level 45 almost immediately, due to 2x and 3x, respectively, experience gain bonus in those Game Modes.
When you are killed by this shape, it will say “You were killed by: Pentagon” instead of “You were killed by: Green Pentagon”.