[3] Toei Animation Producer Atsushi Kido said Fused Zamasu is a "cheat" character for his massive strength, and that his one weakness could be that he was originally a single person.

[6] The resulting fusion is later revealed to be flawed as Fused Zamasu later degenerates into a grotesque appearance with the left half his body turning into purple sludge.

In the anime, Infinite Zamasu is an incorporeal energy being while the manga version is an evolved form of Fused Zamasu, his regeneration ability becoming advanced enough to the point where he is capable of creating seemingly infinite fully grown clones of himself from each cell in his body within seconds, after both composite beings successfully and permanently merged at a cellular level.

[10] Marsters did not provide confirmation as to whether he is the English voice actor for Zamasu in Dragon Ball Super until a Fan Expo Canada event in October 2021.

[10] Outlaw described his voice in the anime dub to be very similar to his friendly, dulcet tones for Goku, but noted as more sinister and twisted.

This transformation also enhances his energy control, allowing him to refine his weapon forging skills, from creating a huge sword from his palm, to a long scythe capable of tearing holes in the fabric of space-time, summoning copies of himself.

[17][18][19] Black momentarily engages Goku before being drawn back to the collapsing portal while destroying the time machine, realizing the fight has allowed him to become better accustomed to his new body.

[22][23] Both the encounter and news of the present timeline's Zamasu inquiring about the Super Dragon Balls and Goku adds further depth to the mystery as Goku, Beerus, Whis, and the Seventh Universe's Supreme Kai stop him from murdering Gowasu with Beerus believing he solved the crisis by completely destroying Zamasu which would negate future versions of himself.

Trunks then gains power from every remaining living thing on Earth, generating a Spirit Bomb that he channels into his sword to slice Fused Zamasu in half, destroying his body.

The anime depicts him as an energy being that gradually consumes the future multiverse, while killing off everyone on Earth, save Goku, Vegeta, Bulma, Trunks, Mai, Gowasu, and the Supreme Kai of Universe 7.

He was brought back by Fu, and is recruited by Hearts alongside four other dangerous criminals from the Prison Planet, as part of their plot to obtain the Universe Seed and destroy all the deities.

The Goku Black incarnation of the character is particularly popular, placing fourth by fan vote in a poll of Dragon Ball antagonists published by the March 2018 issue of V Jump.

[46] Kotaku staff praised the design of Goku Black's hair, and consider Zamasu and his incarnations to be "easily some of the best villains in Dragon Ball history".

[49] Gibbs opined that Zamasu smartly planned ahead and exploited the most overpowered elements of the series that its own protagonists had ease of access to, such as Saiyan powers and the Dragon Balls, and argued that he didn't really lose in the traditional sense since an entire timeline and all life in it had to be erased by Zeno in the process.

[49] Nick Valdez from Comicbook.com thought Zamasu's elitism, which sees the character falling from grace through an initially noble idea, and his Goku Black persona helped him stand out over previous villains in the franchise.

[51] Stefan Sgarioto from Madman Entertainment ranked Goku Black the sixth most memorable villain of the Dragon Ball series and praised the design of his Super Saiyan Rosé form.

[52] Simon Alvarez from The Inquisitr praised the fight between Vegito and Fused Zamasu and considered it one of the best animated battle sequences in the Dragon Ball Super series.

[53] Shawn Sharis from IGN considers the final blow delivered to Zamasu by Trunks to be one of the greatest moments in Dragon Ball Super.

Valdez noted that it differs from Nozawa's performance in the original Japanese version, and that Schemmel has twisted his Goku voice to frame the character in a "destructive and disturbing light.