Worlds

In The Rising of the Shield Hero, a world refers to a self-contained dimension within the multiverse.

Overview
According to an ancient tome within the Ancient Labyrinth Library, in the universe, there are many different dimensions or "worlds" floating around. Due to their free-floating movement, these worlds very rarely impact each other. During these impacts, the worlds start to fuse and bleed into each other. If these "waves" are not repelled from both sides, the stronger world will consume the weaker world. Naturally, these events are extremely rare - like two stars in space directly hitting each other. However, someone has since directly manipulated the worlds to force repeated "waves".

There are two main categories of worlds within The Rising of the Shield Hero: Earth-like Worlds and Hero Worlds. Earth-like Worlds are where the summoned Legendary and Vassal Heroes are originally from. They all have a Japan which use the same type of Japanese. These worlds are typically more technologically advanced but lacking magic use. The Hero Worlds are worlds where the summoned heroes are sent to. These worlds contain the Legendary Weapon system, Dragon Hourglasses, Guardian Beasts, and magic. There seems to be some other interaction between the worlds besides the waves since heroes often experience media such as video games or books which are very similar to the world to which they will be summoned. Some of this is due to the Legendary Weapon's influence (such as through the book "The Record of the Four Holy Weapons" through which Naofumi was summoned. The rest seems to be from the organization behind the waves. The media created from this group (like the video games Ren, Itsuki and Motoyasu played) is ostensibly helpful information a first but ends up leading them astray.

When travelling between different worlds, the traveller's stats are reset to the first level. Any characteristics tied to level (such as appearance) may also be reset. The geography and rate of time can vary between the Hero Worlds.

List of Worlds
This section is a list of all mentioned worlds in the shield hero multiverse. Note that this list is not exhaustive and it is implied that there are more.

Naofumi's World
The world which Naofumi originally came from seems to be identical to our world in the modern day. Compared to the other Japans, it is slightly behind in technology and no widespread powers available to the public. However, Naofumi did seem to display the ESPer ability "Nullify Sickness" and "Animal Whisperer" before being summoned to Raphtalia's World. Naofumi often makes cultural references which other heroes do not recognize such as Rip Van Winkle, chocobos and Superman.

Itsuki's World
Itsuki's world is unique when it comes to the world of the Legendary Heroes. While it has similar technology like comic books, console games and trucks of Naofumi's world, some people of this world have special ESPer powers. These powers started to appear about 25 years before Itsuki was summoned and can manifest in a wide array of power and effects. These powers have become a source of division in this world as even schools are divided by ESPer power potential. These powers are spreading although most people still don't have powers. Use of ESPer powers are also heavily regulated. A popular console game in this world is Dimension Wave.

Ren's World
Ren's world is more technologically advanced and seems to have a faster rate of time than the other Japans. Of all the heroes, this world seems to have the most similar cultural references to Naofumi's world however, they are considered a bit dated. One widespread piece of technology is the immerse VR technology which can be used to watch movies or play the VRMMO games which have taken over the market. A popular VRMMO game is called Brave Star Online.

Motoyasu's World
Motoyasu's world seems the most similar to Naofumi's world in that it has similar technology and no other "power" system like Itsuki's ESPer abilities. However, this world is still distinct with its own history and different prime minister that Naofumi's. A common game is called Emerald Online

Kizuna's World
Technology-wise, Kizuna's world is in between Naofumi's and Ren's world. While her world doesn't have wide-spread full-dive headsets, it does still have VRMMO technology. However, to use it one must enter of fluid-filled pod prepared by the game company. Christmas does exist in Kizuna's world since she named her shikigami Chris after the holiday.

Raphtalia's World
Raphtalia's World is the main world where Naofumi, Ren, Itsuki and Motoyasu were summoned. It consists of multiple countries with Melromarc being the largest. Its residents include humans, animal-based demi-humans and beastmen. The residents of this world use magic extensively but have not progressed significantly technology-wise. This world is the result of four worlds fusing together where the Legendary Bow and Shield worlds merged and the Legendary Sword and Spear worlds merged together. Afterwards, the two resultant worlds merged into the world that existed as of Naofumi's summoning.

Glass' World
Glass' World is the world where Legendary Hunting Tool user Kizuna was summoned to. Residents of this world include humans, jewels, spirit people, dwarves and elves. Compared to Raphtalia's world, the magical technology has advanced to a point where traditional ritual magic has fallen out of favour. Three of the four summoned Legendary Heroes have been killed as of Naofumi's return to this world. Time flows about twice as fast in Glass' World so that one month in Glass' World is equivalent to two and a half weeks in Raphtalia's World. The experience gain rate is also boosted. This world is also a result of four worlds merging however the order is unknown.

S'yne's World
S'yne's world is a previously existing world that was destroyed by a wave due to interference from the organization behind the wave and S'yne's Sister. This world contained celestial-like demi-humans and was the result of at least 2 worlds merging.

Leader behind the Wave's World
This world is where the organization behind the wave resides and is the result of at least 2 worlds merging. Not much is known about this world except that only one Legendary Hero is alive but is captured but the organization behind the waves. A "terrorist" group tried to kill the last Legendary Hero and thus destroy that world but was stopped by Malty and her followers.