Defeating a set number of portals within a given Floor is one of the possible objectives to choose from during a Spire run.
Description
Portals are small inky orbs each encased within a larger semi-translucent orb perched upon thin, stacked Jelleton pieces. Various disassembled Jelleton pieces "swim" suspended within the translucent part. They seem to be made of the same black grey-ink Jelletons paint with.
As a portal is attacked, it rises further up above while being covered in the player's ink. When defeated, a portal explodes with a very large radius similar to a Booyah Bomb in the player's ink, harming nearby Jelletons.