Dinosaur King
Dinosaur King

Dr. Z (Dr. ソーノイダ Dr. Sonoida) is the main antagonist in the first series of Dinosaur King as the leader of the notorious Alpha Gang. However, after being betrayed by his long-time comrade, Seth, Dr. Z "changes" his ways and "joins" the D-Team's "cause" during season 2. He is voiced by Tetsuo Goto (Japanese) and Eric Stuart (English).

Character Design


As with many members of the Alpha Gang, Dr. Z's Japanese name is a dinosaur pun. In his case, his name "Sonoida" is a reverse of "Dinosaur" itself ("so-no-i-da" flips to "da-i-no-so"). Coincidentally, the similar-sounding Sonidosaurus is a sauropod, though not featured in Dinosaur King.

In English, his name comes from the last letter of the English alphabet to coincide with the Greek letter of Zeta Point and oppose with the Greek letter of Alpha Gang, which references the first letter of the English alphabet (though it's not the last letter of the Greek alphabet).


Dr. Z is the zany, egotistic, and evil leader of the Alpha Gang. He plans to use the dinosaur cards in his plans to fulfill his dreams to become the "Dinosaur King", being obsessed with all things dinosaur. Dr. Z is also very short tempered and very stubborn against listening to opposing ideas (unless the presented idea also praises him), but typically adopts the idea anyway while claiming it to be his own. Dr. Z doesn't take responsibility for his actions, (initially) refusing to apologize for what he did to Rex and his parents. He is also very stingy and clingy, claiming everything he wants to be his and refusing to splurge on expenses (this includes when he sees and presumably recognizes Rex's dinosaur tooth necklace). Though he attempts to be angry at his maid Helga for sometimes interfering with his work, one stern look from her easily intimidates him into silence.

However, in his youthful years he was apparently a kind, generous man, as he had adopted the Alpha Trio and Rod and Laura's father from an orphanage, raising them as his kids despite seemingly never being married. A vein of this shines through every time he sees that one of his Secret Dinosaurs has appeared, having raised each of them (sometimes poorly) and (wrongly) expecting them to love the reunion as much as him. It also takes over whenever his grandchildren Rod and Laura are in trouble.



Living in the future, Dr. Z's early life included his adoption of the Alpha Trio and Rod and Laura's father. Some time later, he became involved in Dr. Ancient's time travel mission to rescue dinosaurs, departing to the Mesozoic on Christmas Day 2127. He subsequent began causing trouble, making the collected dinosaurs fight, secretly creating Move Cards, and raising his own super-powerful Secret Dinosaurs. He interrupts an attempt to return to the future, leading to the timeship crashing in the present and scattering the cards across the world.

Dinosaur King

Stationed at the artificial island of Zeta Point, Dr. Z typically starts off each episode by sending the Alpha Trio to obtain the latest dinosaur card that has activated. He usually stays in his lab, working on inventions (some relevant, some not), locating the next card early with dinosaur bone chants, or complaining about the Trio's failures. In early episodes, he spent his time recreating Move Cards for the Trio to use, and also seems to be behind most of their vehicles and other technology (which are infamously often single-use). Despite his tech genius, and though building the robotic Helga from an online kit in the future, he knows nothing about how her programming works and has no way to fix her when she goes haywire starting in Planes, Trains and Dinosaurs.

Being so absent from the field, the first time the D-Team meet him is when they (accidentally) sneak onto Zeta Point on their own in Alpha's Zeta Point. On rare occasions, however, he will join his team, typically when one of the Secret Dinosaurs he raised appears (eps. 14, 28, & 34), who he gleefully tries to reunite with, but who usually run away or fight back. He also leads the team on important (or easy) missions, such as retrieving the Dinomond Amber from New York in The Big Apple Grapple and dealing with the Doppelganger Alpha Gang in Double or Nothing. Though usually telling the Alpha Trio to summon their dinosaurs, when he does take up an Alpha Scanner, he typically summons Terry, and occasionally Spiny.

In Metal Imbalance, however, when Tank cracks open a boulder of retrieved Alpha Metal ore, he catches a falling chunk of it and throws his back out, leaving him bedridden until A Kyoto Caper, when he jumps up to accompany the mission to Kyoto and see the geisha—I mean, to find the last dinosaur card, yeah that's right… (It's implied he may have fully healed earlier but was milking it.)

As revealed in the first season's finale arc, Dr. Z and the Alpha Gang are from the future, using the Backlander, the timeship hidden under Zeta Point, to reach the time of the dinosaurs. They worked for Dr. Ancient and Dr. Cretacia, Rex's real parents, who wanted to save the dinosaurs with the Element Stones they'd discovered, but during the mission, Dr. Z creates Move Cards and begins using the dinosaurs to fight each other, trying to form a dinosaur kingdom for himself. When Ancient and Cretacia try returning to the future following Rex's birth, Dr. Z suspects they'll use the opportunity to kick him off the mission and, mutinying with Seth, ejects them mid-flight, Jonathan interfering to protect Rex but dislodging the Stones, forcing the Backlander to crash in the present and scattering the dinosaur cards across the world, baby Rex and Jonathan landing 12 years earlier in the timeline.

During the arc, Seth betrays Dr. Z before Dr. Z can betray him and take credit for his work like he did Dr. Ancient, kicking Dr. Z and the Alpha Gang out of Zeta Point. Dr. Z begrudgingly allies with the D-Team when Seth uses the Backlander to fly his newly created Black T. rex to Sanjo City, where, after Rex saves him from being eaten by the behemoth, he apologizes for what he did to Rex's parents. He helps summon dinosaurs into the small army to face the Black T. rex (Terry, Saurophaganax, and Daspletosaurus). After the Secret Dinosaurs are summoned as well, he tries riding Pachycephalosaurus, but gets thrown off the ship by the rambunctious dinosaur (his Alpha Scanner grabbed by Dr. Taylor) and gets caught by the Alpha Trio in Reese's plane, taking no further part in the battle.

After the day is saved, it is revealed that Drs. Ancient and Cretacia have seemingly been secretly kept in stasis on the Backlander the whole time, possibly rescued by Dr. Z before the crash, perhaps out of hidden guilt (though no answer is actually spelled out, and they may have instead returned from the future on their own somehow, as implied by a later recap intro). However, he and the Alpha Trio are "confined to quarters" for their past bad behavior for the timeship's return trip to the future…

Mesozoic Meltdown

…but are immediately forced back by the attacking Spectral Space Pirates. After the Pirates kidnap the D-Team's parents, Dr. Z "generously" agrees to help repair the damaged Backlander to follow them, instead accidentally sending them flying through the timestream without destination control (and leaving Rod and Laura in the present). Crash-landing in the Cretaceous, he immediately tries being evil again and sends Terry after wild dinosaurs, but Terry is beaten by Chomp and other wild dinosaurs, and the Alpha Gang are cornered by Ace and Paris before everyone retreats from the approaching meteor.

In the season that follows, Dr. Z and the Alpha Gang take a backseat for plot relevance, mostly being trapped in side antics, though he spends far more time out of the Backlander than last season, typically while accompanying the Alpha Trio on their side quests.

Upon seeing Torvosaurus' Spectral Armor in Ancient Roman Holiday, he sets to work on counters during the Ancient Rome arc, giving the D-Team new and stronger Moves in Desperately Seeking Spartacus and debuting the Element Boosters to provide DinoTector Armor in There's No Place Like Rome.

In the Caribbean Sea Arc, he first jumps into the action in Dinosaurs of the Caribbean to help Ace against Gabbro's dinosaurs where he managed to use Terry to defeat Gabbro's Edmontonia with Ultimate Fire. Following Helga forcing them to return for sunscreen, he takes on the persona of the high seas pirate "Whitebeard" at the helm of the Alpha Pirate Ship for the rest of the arc, getting into arguments with the British Navy, pulling the steering wheel off during a storm, refusing to cooperate unless he's called "Whitebeard", etc.

In Ancient China, he (with a time travel variant of seasickness) drags the Alpha Trio after a dinosaur, ramming into Foolscap's ship and crashing. They, in order: are mistaken as wizards by the locals and hear about the Fruit of Eternal Life, but let slip they're not wizards and get chased out of town (Four Part Harmony); eat unripe peaches thinking they're the Fruit of Eternal Life and get mistaken for Sanzo Hoshi and company (Dr. Z as an older student), but bring underground lava instead of underground water to the village crops and get chased out of town (Elements of Surprise); and pretend to be Sanzo and company on purpose (Dr. Z as Sanzo this time), but Dr. Z gets grabbed by Gabbro to chant a boulder away from a cave entrance and is discovered as a fake, his cape being stuck between two big rocks (Monk in the Middle). In The Third Cosmos Stone, the real Sanzo is dragged in and argues to let Dr. Z go before his cape slips free, dropping him into what appears to be Lotus Land, home of the Fruit of Eternal Life, but he falls off a branch reaching for the biggest peach, landing amidst the Alpha Trio.

He is kept aboard the ship in Ancient Japan by Helga because he refuses to finish eating the bowl of mush she made for him to eat, so he sends the Alpha Trio to get him a new dinosaur card to ease his suffering. They find and are chased by bears instead.

In Ancient Persia, he accompanies the Alpha Trio into the 40 Thieves' treasure cave, but they get caught stealing by the Thieves, and in the next episode are forced by Zayid to attack the D-Team to capture Princess Zahrah, but fail. Dr. Z is then locked up in the palace dungeon with the Sultan, being used as leverage to make the Trio fight the D-Team again, but he is eventually rescued by Aladdin, thinking him the Sultan, trying to flee before the dinosaur fight breaks the water tower and floods the dungeon. He and the Trio almost catch the Red Cosmos Stone but are retrieved after the battle by Helga, who drags them back to do laundry on their dusty clothes.

In the Renaissance Paris Arc, he sends the Alpha Trio to get the Green Cosmos Stone under the guise of getting French bread, now seeking the Cosmos Stones' power to become Dinosaur King. He has no further role in the arc beyond it being revealed in All For One that he'd adopted the Alpha Trio as toddlers along with Rod and Laura's father.

In the finale arc, he goes off on Seth after his return, but is distracted by the gel chibi dinosaur he brought with him. He races headlong into the plant-and-insect-filled alternate present in The Forestfire Effect to rescue Rod and Laura, but no one brought an Alpha Scanner, Helga saving them from a giant mantis. He is unable to grab the Black Cosmos Stone in The Search for the Last Cosmos Stone before the volcano erupts, but retrieves it from the mammoth skeleton later and "heroically" agrees to become Dinosaur King with it so he can rescue the D-Team's parents (Max takes the Stone to trade a copy for them instead). With Seth back onboard the Backlander in Clash for the Cosmos Stones, Dr. Z makes a new Move for Max to defeat Cryolophosaurus with, and protests the D-Team trying to trade the retrieved Cosmos Stones again. Back in the present, he chases Seth with the stolen Cosmos Stones into the D-Lab before Armatus wrecks it with Spectral Stinger, Helga pulling him from the rubble next episode in the finale, Fate of the Cosmos. He suggests combining the Stone Plates to combat the combined Cosmos Stones, letting the others break inside the Dark Pterosaur, defeat the Space Pirates' altered dinosaurs, and find the Space Pirate Ship, whose abundant dinosaur life he is immediately distracted by. After the universe is saved, he declares himself the Dinosaur King ruling over all of the dinosaurs he saved from the ship, but, after being given Dr. Drake's giant needle to help care for the dinosaurs, is dragged with the dinos, the Alpha Gang, Seth, and Rex and the Ancients back to the future.

DS Game

In the opening cutscene of the game, Dr. Z and the Alpha Gang steal one of the DinoShots that Reese invented, turning it purple, and using the stolen Stone Fragment to summon a stolen Tyrannosaurus to face the player in the tutorial battle, retreating upon their defeat.

After sending his underlings across the world to gather more Stone Fragments and hamper the player’s efforts during the game (and all of them losing in turn), Dr. Z kidnaps Zoe to ransom for the Fragments, facing the player as the final boss in the Alpha Gang HeadquartersCommand Center in Antarctica. He hands over Zoe and the Fragment after his defeat, but slips away while the D-Team is distracted talking with the spirit voices from the Stones, vowing after the credits that he’ll one day ride on the back of a dinosaur.

In battle, he uses mainly Fire Dinosaurs (the same as Zander, oddly) like Tyrannosaurus, Mapusaurus, and two Saurophaganax. In the finale Arctic game, if you favor a rematch, he uses two Saurophaganax and an Eoraptor.


TCG Stats


Dr. Z TCG card (DKCG)

  • Team: Alpha Gang
  • Card Code: DKSS-032/032, DKCG-146/160, DKAA-074/100, DKBD-075/100
  • Card Rarity: Oversized Exclusive (DKSS), Silver (DKCG), Common (DKAA, DKBD), Thai Common (JCL)
  • Image From (DKSS/DKCG): Ep. 34 anime scene
  • Image From (DKAA): Ep. 20 anime scene
  • Image From (DKBD): Ep. 20 anime scene
  • Image From (JCL): Ep. 78 anime scene
  • Other: Dr. Z shares being the character linked to Terry with Ursula between releases, the only time this happens for a Special Dinosaur. There is a Jurassic Clash Character card featuring both Dr. Z and Helga, though its name isn’t clear.
  • Abilities:
(DKSS/DKCG) Choose a Dinosaur in your discard pile and Dino Slash it. Then, search your deck for a Move or a "Terry" and put it into your hand. (Shuffle your deck after you search it.) You can include "Terry" in your deck only if you are using this Character.
(DKAA) Choose 1 of your Alpha Dinosaurs. It gains +500 Power the next time it battles this turn. Then, search your deck for an Alpha Dinosaur or a Move and put it into your hand. (Shuffle your deck after you search it.)
(DKBD) Choose 1 of your Alpha Dinosaurs. The next time it battles this turn, it gains +400 Power and gains [Bite] if it does not already have [Bite]. (If it wins the battle, your opponent loses 1 extra Life Point.) Search your deck for a regular Move card and put it into your hand. (Shuffle your deck after you search it.) You can include "Terry" in your deck only if you are using this Character.
(JCL) {translation uncertain} {Search your deck for a Normal Move and a Super Move. Put 1 card of each type into your hand, then shuffle your deck.} You can include "Terry", "Spiny" and "Tank" in your deck if you are using this Character.


  • Dr. Z owns underwear with a picture of Helga's face on it, only seen in episode 1 when Terry bites a hole in his pants. Helga has shown her disapproval of the placement.
    • However, this underwear is not in the Japanese version; instead, it shows Dr. Z's bare bottom.
  • He once had a turtle named "Sue". This eventually led him to name one of his Deinonychus "Sue" as well.
  • Dr. Z likes sauerkraut. In episode 19 he wonders if the museum canteen has sauerkraut, and in episode 43 he agrees to drink (and later finish) Helga's sauerkraut and chili broth (ignoring all the extra spiciness).



p · e · t Main Characters
D-Team: Max Taylor · Rex Owen · Zoe Drake · Spike Taylor · Reese Drake
Alpha Gang: Dr. Z · Ursula · Zander · Ed · Rod · Laura · Seth (former) · Helga
Spectral Space Pirates: Spectre · Gabbro · Foolscap · Shear · Seth (former) · Goma