This:

Galatians 1:9 As we have said before, so now I say again: If anyone is preaching to you a gospel contrary to the one you received, let him be accursed.

Any gospel with an adjective in front of it would merit that response.

Why do people claiming the name of Christ preach other gospels?  Paul answers it in the next verse.

Galatians 1:10 For am I now seeking the approval of man, or of God? Or am I trying to please man? If I were still trying to please man, I would not be a servant of Christ.

Just stick to the real Gospel.  If that isn’t enough for someone, he doesn’t understand it.

1 Corinthians 15:3–5 For I delivered to you as of first importance what I also received: that Christ died for our sins in accordance with the Scriptures, that he was buried, that he was raised on the third day in accordance with the Scriptures, and that he appeared to Cephas, then to the twelve.