Board Thread:Supergirl discussions/@comment-31722073-20190520131713/@comment-31722073-20190607114408

Malefic is clearly not a full season villain, but Leviathan is based on a very large current event, they won’t waste it on 9 episodes shared with anyone.

The best and most clear reason for this is simple, Lena is a multi-season regular, if she turns eeeevil she would become Kara’s worst enemy, they would never use her for just 13 episodes, Ben even got 14 episodes before Lex showed up but still villained later, most of the time of his own accord.