Chivas 1-2-3

The "Overlord" TV series bears some similar features to "Chivas 1-2-3", primarily in that both the main characters, Ains and Chivas respectively, are dramatically over-powered sorcerers. Both are also rather egotistical or rather selfishly driven characters. Also both have some rather sycophantic followers. I would also consider both anime to to be "dark fantasy" as a subset of the fantasy genre. 

The anime version of "How Not To Summon A Demon Lord" uses a very similar premise but is different, or maybe "more 21st century" than "Chivas 1-2-3". Instead of the "body-swap" trope it uses the isekai trope to put an otaku into a fantasy world as an over-powered egotistical demon sorcerer. Said sorcerer has two slave girls, much like Chivas' relationship with Fizz and Kiss. One's an elf not to dissimilar in style from Kiss but fills more of Fizz's role, and the other is a cat-girl mage who looks more like Fizz but provides the "furry factor" as an alternative to Kiss's role. That and "How Not To Summon A Demon Lord" has the as much or perhaps more of an ecchi factor to it. read more 

Both "Gestalt" and "Chivas 1-2-3" center on over-powered sorcerers, Ohri and Chivas respectively. They both appear to be rather self-centered and with ulterior motives. Both anime include the theme of slavery, in "Chivas 1-2-3" Chivas appears to have the two female main characters, Fizz and Kiss enslaved to him; both treat him as a master. Likewise, in "Gestalt" Father Olivier is "given" Ohri as a slave, who treats him as a master. Both these shows deal in showcasing magical battle fireworks. They're also contemporaneous classic 90's OVA, if you're looking for that kind of thing.  

Both the main characters in "Orphen" and "Chivas 1-2-3" are generally over-powered and rather egotistical sorcerers. Both generally deal with concepts of powerful sorcerers acting in possibly corrupt ways. They're also contemporaneous products of the 90's and have similar production values.  

old skool fantasy anime that both have a master magician that suddenly comes in a unusual situation , like Fam and Ihrlie use magic and chance temporarly in a mouse,in master chivas case is that he got trapped and share his minion,s body.once again, unusual situations 

"Sorcerer on the Rocks" is a spin-off of "Sorcerer Hunters" (Bakuretsu Hunters) and is set in the same world. Both series fit into the comedy fantasy adventure genre and feature similar types of sword & sorcery action. 

If you liked the main character in Bastard you will also like the main character in Sorcerer on the Rocks (Chivas 1-2-3) as they are almost the same. That attitude, mind and absolutely overwhelming power is there as well. The world in which these series take place is also almost identical dealing with wizards and magic. Bastard is a bit longer as Chivas has only 2 episodes but non the less as they are very similar if you liked one of them you will enjoy the other.