In some sick way Gantz got an abridged version back in 08 to 2010.
There was some high class editing and voice work from Hbi2k in this Abridged as it took all the problems people had with the show and basically turned them into funny skits that make this abridged so memorable. With reffrences to other pop culture and anime and turning Idea's such as Gantz' song introduction "It the Beginning of a Brand New Day." into Rick Astley's "Never Gonna Give You Up." is a brilliant use of the material.
The best jokes come from the Main Character Kei Kurono who in the Anime is a Selfish Teen Pervert and in this Abridged version is a somewhat dorky more sensible archetype of the Anime version, and the best parts come from when he shows off his strength and "badassness" while also creating his own version to the Huallaga chore song.
Throughout this abridged it's hinted that the ending will be the biggest part for the abridge to shine as they make note it's "A Worse Ending than Berserk" and in truth Gantz the anime is infamous for it's "filler" ending (Filler being an episode not in the source material and is often included to justify a 26 episode series)
The last ones instead of being dubbed Gantz Abridged. They are dubbed as GAS: TFC (Which in short means Gantz Abridged Series: The Filler Chronicles)
I enjoyed watching this series back in 2008-2010 and I enjoy it just as much in 2019. I would even say it's better than The Anime itself, but I ofcourse love the anime as well, so I would like to say this is one of those rare cases where a parody can be just as entertaining as it's content it has parodied.