On post #2217579, I provided the tag cynthia_(pokémon), which implicates pokémon_champion. However, when posting it gives the error:
Can't add tag pokémon_champion: Name 'pokémon_champion' must consist of only ASCII characters.

Additionally, since the cynthia_(pokémon) tag was correctly added to the post but not the pokémon_champion implication, every time the post is edited it tries to reapply the implication and gives the error again.