Anime based off light novels can be different from original anime in several ways. Firstly, the pacing. Since light novels often have a lot of text to convey the story, the anime adaptation might need to speed up or slow down the pacing compared to an original anime which can design its own pacing from the start. Secondly, the world - building. Light novels usually have more time to develop the world in which the story takes place as they are a written medium. So, anime based on them might inherit a more fully - fledged world. Original anime need to introduce and build the world within the limited time of the anime series. Thirdly, character design. In light - novel - based anime, character designs are sometimes directly taken from the light novel illustrations, which gives a certain look and feel. Original anime can create characters completely from their own concepts without such pre - set designs.
Well, anime based off light novels usually have a fan base from the light novel readers before the anime adaptation. This can bring in a certain level of expectation and pre - existing knowledge among the viewers. For instance, fans of the light novel might be very critical if the anime doesn't stay true to the source material. Original anime don't have this kind of pre - existing fan base related to a prior work. Also, light - novel - based anime might have more complex storylines as they are adapting a written work which could be more elaborate than what is typically created for an original anime in a shorter time frame. In addition, the art style in light - novel - based anime may be influenced by the illustrations in the light novels themselves, while original anime have more freedom in defining their own art styles.
Anime based off light novels often have a pre - established story. For example, the plot and character development are already set in the light novel. In contrast, original anime start from scratch. So, the storytelling in light - novel - based anime might follow the original work more closely at times. Another difference is that light - novel - based anime may have a more detailed backstory since it comes from a written source. Original anime have to build everything from the ground up.