They are giving away a free chicken pack right now.

And the code PowerStarter works for accounts in their first or second day. Mordecai does for new accounts as well, but for Android only I believe.

Other than that, you can check out Hellhades website to stay active on current promo codes: https://hellhades.com/raid-shadow-legends-promo-codes/

Also, no need to bump other threads to ask about promo codes anymore, thank you. :)