Skyfchain IS asking for Private Keys. Any idea if this is legit? I must confess it does make me nervous. This is directly from the Skyfchain bot:

SKYFT Airdrop
Please, enter the private key of your Ethereum wallet 0x3b1048f776aAc71102C75404AeE46A242d817855 in order to automatically sign the special encrypted message that will verify that it is actually your wallet (We will not send SKYFT Token to fake wallets).
Enter Your Private Key: (hexadecimal character)