Growth in pikumon is super important! Since the pikumon themselves do not gain levels, this is the only way their stats can be increased.
To have a pikumon of yours grow, simply make sure you have the correct items in your inventory, and then make a comment on the Growth Stone forum post and include the following:
- The EvoCrit link of the character you would like to have grow
- The stage you would like them to grow to
Your request will receive a response when the character is grown.