If you liked
E's Otherwise
|
...then you might like
Gilgamesh
|
Both series feature children with Psychic powers.
If you liked
Black Cat
|
...then you might like
GetBackers
|
It's quite similar considering that Both Black Cat and GetBackers share a main English Voice Actor (Jason Liebrecht plays both Train and Ban in both series respectively), As well the music is done by Taku Iwasaki in both series. The fact that both series have goofy characters like Sven and Ginji and the more serious character like Train and Ban. Means this is almost a clone of it.
If you liked
Gantz
|
...then you might like
Red Garden
|
Gantz and Red Garden have very similar plots albeit a little more different, They both feature peope who have died and are given another chance to live if they defeat certain monsters. However, if they die, they die forever.
If you liked
Gantz
|
...then you might like
Death Note
|
Both of these series deal with the concept of Human life and essentially how much it's worth. They both are commentaries on how people devalue human life.
If you liked
Gantz
|
...then you might like
Hellsing Ultimate
|
I think Gantz and Hellsing Ultimate are quite common in both the blood and gore department as well as with the dark comic element in both series.