Expansion is the type assigned to an extension. You can check which expansion is assigned to an extension in MCH Dictionary or other sources.

In Duel Cups and other contents, there may be restrictions on the use of extensions based on the expansion. Restrictions can be found in the cup information.

Expansions may be subject to allocation changes, such as the timing of the WP series switchover.

There are three types of expansions.

• Standard

This expansion is allocated around basic performance extensions that are central to the battle environment.

• Modern

This expansion is allocated around the extensions added in each year.

For example, an extension added in 2024 is basically assigned a Modern expansion within 2024.

As a special exception, extensions added at the end of each year may also be Modern the following year.

• Legacy

Extensions that are not Standard or Modern are assigned this expansion.

• Other points

Limited extensions are assigned the same expansions as the series.

All replica extensions are treated as Legacy.