End gateway

End gateways are portals generated in the End after defeating the ender dragon, and are used to gain quick access to the outer End islands.

Generation


A new end gateway generates near the edge of the main island each time the ender dragon is defeated. On the main island, a maximum of twenty gateways can be generated for each world, arranged in a circular fashion around the island at Y-level 75, approximately 70 to 100 blocks away from the center (0,0). Killing the ender dragon after twenty gateways are generated will not generate further gateways.

An additional end gateway will generate in the outer End regions after activating one at the main island. These gateways generate at Y-level 66 to 69. If there are no blocks within a five-block radius from the gateway below these Y-coordinates however, then it generates above the usual level until there is a block below the structure within the radius. The exact X-Z position where the gateway generates in the outer islands is random, but it is always within ~1000 blocks from the center and relative to the X-Z coordinates of the first gateway and (0,0).

They also generate randomly among the outer islands. These teleport the player back to the location of the original obsidian platform at the central island, though it does not regenerate the platform.

Structure
The end gateway is composed of an end gateway block confined within a small formation made up of twelve bedrock.

Behavior
A magenta beam shoots out vertically from the top and bottom of the gateway when it is generated. The beam disappears after 10 seconds. When an entity enters the gateway, the gateway emits the beam for 2 seconds.

The bedrock arrangement prevents the player from entering the gateway directly. Throwing an ender pearl or flying with an elytra straight into the end gateway block will teleport the player to the outer End islands. Players can also access the inside of an end gateway by constructing a water channel leading into it and sprint-swimming through the channel and into the gateway, or by suffocation prevention. Any entity that moves into the end gateway block also is teleported. Entities riding on another entity (e.g. pigs and minecarts) are unable to be teleported until they dismount.

Once the gateway is activated, another end gateway generates in the outer end islands near to where the player is teleported; this gateway will teleport the player back to the original gateway, providing a way to return to the main island.

The position where the player or entity lands after teleporting is determined by a systematic algorithm: the gateway searches for a non-transparent block starting from the north-west corner at the topmost height (Y=255) within a 5 block radius around the gateway block. If there is a block at that position, then the entity is teleported onto that block. If there is no block, then the next position along the Z-axis is searched (shown as the lapis lazuli block on right). This continues along each column in an 11 × 11 area at the same Y-level with the exception of blocks above, below, or directly adjacent (including diagonals) to the gateway block. If there are no blocks, it moves one Y-level down and repeats the sequence from the north-west corner again. It will continue doing this until every height is checked, and if there are no non-transparent blocks within any of these points it will always teleport the entity exactly two blocks above the gateway block.

Trivia

 * If an end gateway is broken (e.g. in creative), players can still enter the gateway on the other end. This will teleport the player to the broken portal, which does not regenerate.
 * Once an end gateway generates on the main island, the corresponding gateway in the outer islands can generate, even if the player has not yet entered the portal on the main island, or the section of the outer islands has already generated without the gateway.