Magister Patelliday is a Piscciss Volann Plumber. He is the second-in-command of the Plumbers of Earth.
Magister Patelliday first appeared in the The Mother of All Vreedles when the Plumbers took Ma Vreedleto prison.
As Omniverse, he is the second-in-command of theEarth Plumber Headquarters.
He made cameos in The More Things Change: Part 1, Part 2 and in So Long, and Thanks for All the Smoothies.
In Gone Fishin' he was fishing with Max, Ben and Rook in Undertown at the Spaceman's Wharf. After Ben couldn't catch anything he turned into Ripjaws and dived into the water with Patelliday. While they were swimming underwater, Patelliday snapped at a Mechaneer which was covered by fishes. The Mechaneers took him and Ben couldn't save him because the Omnitrix timed out. The Mechaneers took him to a pirate who refused to eat him fresh. They then took him to the kitchen. Patelliday eventually freed himself and with the help of Ben's team they arrested the pirate.
He made cameos in Tummy Trouble and in The Frogs of War: Part 1.
In The Frogs of War: Part 2, after the Incursean invasion, he was taken to custody just like every other Plumber (with the exception of Blukic). He was locked into the same cell as Driba, who gave him his water after he got severely dehydrated. He was rescued by Rook, Kevin, Gwen and Bullfrag. After he got supplied, he joined Rook to defeat Psychobos.
In O Mother, Where Art Thou? , he called Ben and Rook to the Plumbers’ base after Ma Vreedle started a rampage there. Patelliday told Ma that they don’t have the Pretty Boy that she is looking for. Ma then reports the missing of her child and threatens the Plumbers that if they don’t find him she will blow up the sun. Patelliday told her not to worry and put a tracker to her back. He followed Ma in the sewers and told Ben her location.
In Mud Is Thicker Than Water, he and Ben chased Sweet-Eels Sparklefunk, Liam and Tummyhead who were at the possession of top secret Plumber Tech. He knocked over Sweet-Eels, while Ben defeated Tummyhead but they couldn't get Liam (who later revealed to be Lucy). Later, when they arrived Psyphon’s hideout, Patelliday shot Bug-Lite. Lucy told him that Gorvan was the spy, so he commanded the Plumbers to findGorvan.
In A Fistful of Brains, Patelliday told Max and Rook a location where they picked up the sign of Ben’s DNA. However, it was later revealed to be Albedo’s DNA.
In Max's Monster, after Phil left the HQ’s power core, Patelliday commanded the Plumbers to repair it. Later, he was in the Proto-TRUK with Max bringing the Null Void Projector.
In Animo Crackers, Patelliday got annoyed by Ben who was eating and drinking loud while they tried to work. He then told Ben not to mess around with the monitors. Suddenly, Rook appeared and accidentally scared Patelliday. Later, he, Rook and Upgrade failed to stop Animo from escaping.
In Catfight, he was watching Bullfrag and Attea fight at the Plumbers’ Base.
In The Rooters of All Evil, Servantis used his mind powers on Patelliday. Later, Patelliday battled Phil.
In Universe vs. Tennyson, Patelliday tells Ben that they have to let Chadzmuth do his job.
In Weapon XI: Part 2, Patelliday along with Max and the Magistrata entered theNull Void to revoke the Rooters' status and confiscate their base.
In Clyde Five, Patelliday was dehydrated after Vera Tennyson turned the thermostat up in the HQ.
He was seen moving around in his floating aquatic hoverchair at the celebration for Max's retirement, in The End of an Era. Patelliday is retired and scoots around in his chair.
Ben 10: Ultimate Alien
- The Mother of All Vreedles (first appearance)
Ben 10: Omniverse
- The More Things Change: Part 1 (first re-appearance; cameo)
- The More Things Change: Part 2 (cameo)
- So Long, and Thanks for All the Smoothies (cameo)
- Gone Fishin'
- T.G.I.S. (cameo)
- Tummy Trouble (cameo)
- The Frogs of War: Part 1 (cameo)
- The Frogs of War: Part 2
- O Mother, Where Art Thou?
- Mud Is Thicker Than Water
- A Fistful of Brains
- Max's Monster
- Animo Crackers
- Catfight (cameo)
- And Then There Was Ben (alternate timeline; cameo)
- The Rooters of All Evil
- Universe vs. Tennyson
- Weapon XI: Part 2
- Clyde Five
- Rook Tales
- Breakpoint (cameo)
- Stuck on You
- The Final Countdown
- The Most Dangerous Game Show (cameo)
- The End of an Era (future; cameo)