This mod adds custom dimensions for different periods of times and creatures from these periods. Thay can be revived using genetics in the overworld or can be found in the dimensions by building a portal. This mod includes several ores that you can use to revive creatures. This mod's main goal is to provide somewhat accurate prehistoric dimensions while focusing on performance.
This is meant to be for my custom modpack so I do not advise it's usage standalone as it is experimental!!!