What is this monster?

[TwoTankAmin]

I was not even sure what plant you meant. The one I thought you meant was the taller one with the long leaves which I believe is one of the long leaf Hygrophilias.

Long leaf Hygrophila typically refers to fast-growing, hardy stem plants like Hygrophila angustifolia (Willow Hygro) or Hygrophila corymbosa (Temple Plant), popular for aquarium backgrounds. They feature long, narrow to broad bright green leaves and, under high light and nutrient-rich conditions, can grow up to 20 inches

 

[Slammin’ Aquascaping]

Looks like a Pogostemon. I don’t have this exact species but looks very similar.

Upon my brief research, I think it is a Pogostemon Stellatus. Some people call it Pogostemon Octopus