The similarity between the two is further reflected in the manga. In this manner, the effect of "Avatar" is the reverse of "Ra's" which has several effects to gain ATK such as using all but 1 of your Life Points for its effect and gaining ATK by sacrificing monsters (including its Tributes) in the anime and manga, while "Avatar" only has one where the ATK and DEF of this card was only 1 point higher than the strongest monster (both were changed to 100 for the TCG/OCG). In other words, "Avatar" needs monsters alive to be stronger while "Ra" needs monsters Tributed to become stronger. This card actually became stronger in the OCG/TCG, while "Ra" became weaker.
In the original manga artwork, there was a ghostly image within the sphere, which was removed in all real-life printings.
In the manga, this monster changes its form depending on the strongest monster on the field, changing into a black version of that monster. If a "Metal Devil" is the strongest monster on the field, the "Avatar" would instead take on the form of the player's whose Life Points it represents - Yugi in that case.