Plantera

Plantera is a Hardmode boss. After at least one of either The Destroyer, Skeletron Prime, or The Twins has been defeated, a pink bulb will appear somewhere in the Underground Jungle. Destroying this bulb, which requires a Pickaxe or a Drill will summon Plantera.

The fight against Plantera takes place in two parts. In the first part Plantera will chase the player around the jungle, using its hooks to move around. In addition, Plantera will fire thorns at the player, as well as spitting out the occasional bouncy spiky ball.

Once Plantera is brought down to half health it will change form, the pink bud falling away to reveal a thorn-filled mouth. In this second form it retains its previous attacks, but will begin to move around quicker and more erratically, as well as sprouting a number of tentacle mouths which stretch outward on thin strands, similar to the Wall of Flesh's "Hungry" minions, though the tentacles do not detach when damaged, instead simply being destroyed. Second form Plantera will also release floating pink spores that will slowly drift after the player, similar to the spores released by the Giant Fungi Bulb enemy.

When Plantera is defeated for the first time it will always drop a Grenade Launcher with Rocket Is for ammo, as well as the Temple Key. From the second time onward the drops become randomized.

Tips

 * The pink plant used to summon Plantera is named under Plantera's Bulb on the map.
 * The pink plant glows pink, making it easier to find.
 * Destroying the Plantera's Bulb with an explosion will not cause Plantera to spawn.
 * Plantera can be brought to the surface. The fight may be easier if an arena is built on the surface and Plantera is fought there.
 * Plantera's Bulb can spawn in player made jungle biomes. This could prove as a good way to fight Plantera in a more controlled environment, away from jungle mobs, hazards, etc.

A cheap method of defeating Plantera with little risk can be found here
 * Plantera can be summoned indefinitely, as destroying its bulb will cause a new one to spawn eventually. (Not instantly, as tested on a world with 95% of underground jungle replaced by mushroom)
 * If Plantera is currently summoned and you break another bulb, a second Plantera will not be summoned, and the bulb is destroyed.
 * If the player strays too far away from Plantera, Plantera will despawn.
 * If Plantera has no surfaces to latch onto, the body of Plantera will slowly float off, going up into the space portion of the map, or until it hits a space where it can latch onto again. This can cause the loot from the boss to be unreachable in some cases.

Trivia

 * The name "Plantera" is a parody of the American thrash metal band Pantera. The name originated from Pantera as this is Redigit's girlfriend's favorite band.
 * Plantera also drops "The Axe", which looks similar to the Washburn and Dean electric guitars often used by the late Pantera guitarist Dimebag Darrell. It could also be a reference to Marceline's Axe Bass from Adventure Time.
 * Plantera's boss music also consists of heavy usage of electric guitar, the basis of metal music.