Duck "Bill" Platypus was perhaps the feistiest member of the Downunda Freedom Fighters, joining the group after growing up as an orphan. At one point he was under the mind control of the villainous Crocbot and turned against his former team. However, when Crocbot's plot was discovered he returned to normal and rejoined the Downunda Freedom Fighters. He later participated in the battle against the Bunyip and against the Xorda during their attack. Some time later, Bill was pressured by the local platypus population to join the Eggman Empire and rule them as Grandmaster of the Platypus Downunda Dark Egg Legion, which he reluctantly did realizing he could lead them to defeat. Eventually he informed his former team of this, though he continued to act as the Platypus Legion's leader to ensure their future defeats.
As a child, Bill was part of a group of orphans that also included Barby Koala and Vector the Crocodile, who were all raised by an individual they thought of as their father. Eventually, however, Vector left his "siblings" and Downunda behind, something that Barby and Bill resented him for. (SU: #11, #12, CSE)
Battles Against Crocbot
Bill was the third person to join the Downunda Freedom Fighters, joining forces with Walt Wallabee and Guru Emu while investigating the mass capture of numerous Downunda Mobians. After the prisoners were freed and the team was joined by fellow investigator Wombat Stu and Barby, who had become a mercenary, Bill teamed up with the others in doing battle with Crocbot, even managing to destroy one of his fortresses. (StH: #103)
Their war with Crocbot raged with little variation for some time, until Miles "Tails" Prower arrived in Downunda. With his help, the Downunda Freedom Fighters were able to destroy Crocbot's main base, and seemingly destroyed their old nemesis by knocking him into the Great Crater of Dowunda with an explosive. (TMS: #2, #3)
Crocbot later returned with even more power, capturing Bill and his teammates with an army of Combots. While Bill was his prisoner, Crocbot fitted a microchip behind the Platypus' ear that would activate a post-hypnotic suggestion, rendering Bill his obedient servant. With the aid of Knothole Freedom Fighter members Bunnie Rabbot and Antoine D'Coolette, however, Bill and the others were freed and managed to overthrow Crocbot once again, destroying his Combot army and prison camp in the Great Crater. (StH: #61, SSS: #4)
Under Mind Control
During the Dowunda Freedom Fighters' clean up efforts following their battle in the Great Crater, Bill came across Crocbot's remains, which triggered his hypnotic implant. He began expressing random fits of anger, and eventually went renegade. He recruited a horde of other platypuses to do his master's bidding, attacking the clean up site to scavenge parts while the severed torso of Crocbot remained hidden and waiting to be rebuilt. After luring them into an ambush under the pretense of a truce, Bill captured Guru Emu and Wombat Stu, prompting the Downunda Freedom Fighters to send for help. Sonic the Hedgehog and Tails traveled to the crater where Crocbot had been destroyed prior, and found a slave labor camp where the duckbill army using as a site for Crocbot's new base. The Freedom Fighters managed to unearth Crocbot's remains and take him offline, removing any hypnosis from Bill and the others. (StH: #61)
Fighting Bunyip and the Xorda
Bill and his teammates were soon faced with the tedious task of selecting a new teammate after Wombat Stu left the group to join Geoffrey St. John's new Royal Secret Service. However, a warning given by the defeated Crocbot before he was shut down came true as they were forced to confront the Bunyip, a massive and ancient creature thought to be a myth. Seeking vengeance on Crocbot for imprisoning it with a dam constructed as one of his bases, the Bunyip ended up lashing out against innocent bystanders instead. Bill and the others fought it, but proved unable to defeat the creature through force. However, they were able to reason with it thanks to Barby Koala's knowledge of its language, and in destroying the dam they allowed it to go free. Pleased with their success, the team decided not to take on a new member after all. (StH: #103, #104, #105)
The Downunda Freedom Fighters, Bill and the returned Wombat Stu included, were among the many Mobians who gathered at Mobius's Southern Tundra in order to destroy the Quantum Dial weapon set there by the Xorda. Bill was among the many receivers of the aliens' broadcast of impending destruction, and thus charged valiantly into battle alongside a vast myriad of other Mobians. Following the dial's destruction and Sonic's apparent sacrifice, Bill and the Downunda Freedom Fighters returned home. (StH: #124, #125)
Months after the Xorda's attack, Dr. Eggman made another push to gain control of Downunda. The platypus people saw this as a chance to come out on top if they worked for the Eggman Empire, and pressured Bill relentlessly to be their leader in this endeavor, as he had led them once before. Since Bill was unable to dissuade them, he swore allegiance to Eggman, becoming the Grandmaster of the Downunda Dark Egg Legion and the region's Sub-Boss. His true objective however was to secretly hamper the dictator's attempts to seize the continent, leading to his ineffective leadership of the Legion. Since he was unable to contact his teammates and let them in on his ruse, it appeared as though Bill had really betrayed the rest of his team. Despite hindering the Empire's advance through Downunda, Bill was forced to make some progress occasionally or he would have been discovered. (SU: #11, #12)
Bill eventually teamed up with Dr. Finitevus and used the Legion to help him capture the Downunda Freedom Fighters and Chaotix. After Finitevus left to study the Master Emerald, Bill dismissed his men, giving himself a chance to free his former comrades. He then explained what had really happened to lead them to their current situation. They agreed to continue the masquerade, "imprisoning" Bill and escaping to scatter the Legion. With Finitevus defeated and the Island released, the Freedom Fighters became even more determined to defeat the Legion-though without "crushing" Bill. (SU: #11, #12)
Later on, Snively sent out a message with the news that Sonic had killed Eggman and that the Dark Egg Legion was officially disbanded to all the Dark Egg Legion's Grandmasters around the world, while the rest celebrated Eggman's death, Bill tried to write a letter announcing peace, only for Eggman to teleport all the Grandmasters-including the spy Duck Platypus-to the Death Egg Mark 2, where he gave them the unwelcome news that he was still alive, and openly reminded them that their robotic parts can be ordered to self destruct with a single command, something that startled the double agent. After telling them of their primary objective of expanding the empire and to search for the missing blue Chaos Emerald, Eggman returned Bill and the other Grandmasters to their homes.(SU: #37)
Bill, like his fellow Freedom Fighters, has a strong hatred for Dr. Robotnik and his regime. He is also a loyal companion to the other Downunda Freedom Fighters, particularly Barby Koala, with whom he shares some history, and a bond that could be "sibling" affection or something more. He also harbors some bitterness towards Vector, whom he may have considered a brother only to have Vector betray that trust by leaving Downunda. Though he acted tyrannical in keeping with his role as Dr. Eggman's Sub-Boss, he genuinely regretted his part in the conquest of Downunda and apologized profusely to his comrades after revealing the truth to them. He also seems to harbor some connection to the other Platypi of Downunda, given that he thought to rally them when influenced by Crocbot and grudgingly agreed to lead them when they joined the Eggman Empire.
It is stated in the in the Complete Sonic Comic Encyclopedia that "He seems to have something going on with Barby." This deeply implies a romantic relationship between the two.
- During the Mobius: 30 Years Later story arc, a character somehow related to the separatists of Mazuri named "Bill" was mentioned by Knuckles the Echidna in SU #5. Whether or not this Bill is the same as Duck "Bill" Platypus has yet to be confirmed.
- Bill, while in uniform, doesn't have any visible cybernetics, unlike the majority of his fellow Grandmasters. However, the fact that he was startled by the knowledge of explosives embedded in the devices is indicative that he does indeed possess some.
Bill is a teal platypus with a darker bill, tail and front. His tuft of hair ends in orange tips. Originally, he wore shoes similar to those of Sonic, featuring a yellow stripe, in purple or red (though he was sometimes drawn with generic red/brown gloves and boots), as well as a simple headband featuring a buckle. In most of his original depictions, his body was stout, largely lacking distinction between his head and torso. In later appearances, he wears an Eggman-styled uniform, though in purple rather than Eggman's red, as well as goggles. His hair has become spikier and more distinct and the proportions and shape of his body have been redefined to better fit in theme.