Envyathan has the appearance of a gigantic plesiosaur. His body is primarily a dark green, with dark teal spots on his forehead, back of his neck, back, and his tail. He has a light tan underbelly. His tail has two light yellow fins that come off of it in an arrow shape. He has an underbite, and his uneven, sharp, yellow teeth stick out. He has four gigantic fins that are lined with barbs.
Evnyathan wears the Omnitrix on a black neckbrace on the lower part of his long neck.
- Envyathan has the ability to manipulate the sin of envy, as well as induce his opponents with envy. This can be used in a variety of ways, such as causing opponents to become envious of Envyathan himself, or become envious of some other individuals.
- Interestingly, this power can work on duplication species to make the clones envious of one another, despite being the same.
- Envyathan can breathe underwater and is a rather fast swimmer for his size.
- Envyathan is equipped with a strong jaw and sharp teeth.
- Envyathan is a large creature, coming from the largest species in the Anur System. This size gives him a high amount of strength and durability, allowing him to take on a To'kustar.
- Envyathan has a rather long neck.
- Envyathan's eyes are equipped to see in the dark.
- Envyathan is resistant to extreme temperatures.
- Envyathan's fins are lined with barbs large enough to impale a human.
- Envyathan's envy powers do not work on opponents that cannot feel emotion, and thus would not feel envy.
- Envyathan's large size makes him an easy target. His size also makes him overkill, as most underwater situations would not require such a large creature instead of a more reasonably sized alien such as Ripjaws or Water Hazard.
- Envyathan's name is a play on the words "envy" and "leviathan."
- Envyathan's species name is a play on the Scottish Gaelic words "farmad," meaning envy, and "uilebheist mara," meaning sea monster.
- Envyathan's planet name is believed to be a play on "Gillman."
- Envyathan takes inspiration from both the Biblical Leviathan, and the Loch Ness Monster.
- The decision to do this was made in order to keep with the idea of Anur Millgan being home to some kind of sea monster without being too similar to other water aliens, particularly Ripjaws, who is quite similar to the Gillman.
- In Christianity, the Leviathan is the symbol for envy, which is where the inspiration for Envyathan's powers came from.
- Envyathan is one of the only two Anur Aliens in the Omnitrix to not have his species and planet share etymology, the other being Ghostfreak.
- Initially, Envyathan's power set was going to be something along the lines of shapeshifting, to play off the numerous possibilities as to what the Loch Ness Monster really is, and how much they vary from one another. The idea was scrapped cause it just wasn't hitting, and Leviathan lore was researched instead to determine a better power.