Area 11 Logo
The logo was stated by Sparkles* on Soundrop to have been created by someone named 'Lee'. Nothing else is known about this person.
In 2018, a new version of the logo was used, ditching the digital eye. It appears like an "A" split by two lines, likely being the "11" in the name.
This is what could possibly have been a very early version of the Blackline EP and may just have been used internally, never intended for public release. Despite this, the artwork for it from its Last.FM Page can still be found.
The symbol in the eye appears to be that of a Geass power from the anime Code Geass, the anime from which the band takes their name. The symbol appears in the eye of someone who is using a Geass power.
The cover for Blackline is believed to be of Cassandra, however it may also be of Euphemia (the character) from the anime Code Geass. It has been stated by Sparkles* on Soundrop that the artwork was created by an unknown illustrator, who is not otherwise related to Area 11.
The cover for All The Lights in the Sky seems to be inspired from the anime Tengen Toppa Gurren Lagan.
The ATLITS art was created by Adam (a Yogscast editor) however when he admited to creating it S* quickly said it was based from a photo he had found, then quickly changed what he said, saying it was sent from a mysterious email.
It is believed that the figure on the cover is Cassandra.
Another question is whether or not the headphones are plugged into anything, when asked Sparkles* has not given a clear answer.
The continuation of the "Lights in the Skies" between the two different album covers was, according to Beckii, intentional. Who confirmed it to her is unknown, but most likely to be from Sparkles*. Why they changed the cover for the continuation to happen is unknown, although it may be because it was the finalized version of "All the Lights in the Sky".
The art for Shi No Barado was also created by Adam .
The numbers and letters in the bottom corner are 61646d696e/69206d756e6375317573 which is decoded to admin/h0muncu1us. Homunculus, which refers to a representation of a person, was also originally a track that was supposed to be on ATLITS.
The scratched-out numbers are 6134, the meaning of this is still unclear.
On the back the album has these Japanese characters: 大きな男の子のシングル which means "Single of the big boys". Sparkles* told a lengthy story of the meaning of this on Soundrop.
The artwork also features an archway with 11 stones, the sixth of which is the keystone. Interestingly Shi No Barado is the 6th song on ATLITS. This archway later featured on tour merchandise for the Ni Tour.
The cover art for GOFAP. No easter eggs have been found so far.
This artwork originates in a 2009 photo from Sparkles*' Deviantart account. The landscape beyond the lake itself looks like a waveform, so it probably inspired the artwork's premise in the first place. The 2009 upload date means that Echodeath cannot have been finalized before 2009.
The artwork for Underline features a red and black background of cloud-like shapes, with a white line running horizontally across. This could be the aftermath of an explosion, or an empty area of outer space.
The artwork for Modern Synthesis resembles the chart for the idea of Modern Evolutionary Synthesis, seen here.
The album art for the EP is a modified version of the Modern Synthesis cover, with "Let It Resonate" in place of "Modern Synthesis," and an acoustic guitar in the background. At the top of the acoustic guitar seems to be a hand, likely either Sparkles*' or Kogie's.
The album art for this single is a woman with a scaly shirt and no pants in a bathtub half filled with water. The picture is blue-tinted, and a blue version of the 2018 version of the Area 11 logo is overlayed.