What is the gospel Paul calls 'my gospel'?

The gospel Paul designates as 'my gospel' is the gospel of grace, also called the gospel of Christ and the gospel of God. It differs from the gospel of the Kingdom that Jesus and the Twelve proclaimed to Israel. Paul preached it in virgin territory, not as an extension of the Twelve.

Les explains that most of Christendom today, without realizing it, preaches the gospel of the Kingdom rather than the gospel of Christ, leading many down a wrong road. They are not hearing the gospel of grace, the gospel of Christ, the gospel of God—what Paul calls 'my gospel.' By contrast, the gospel of the Kingdom was proclaimed by Jesus and the Twelve to the nation of Israel. Paul states he is not boasting beyond his measure or building on other men's labors, meaning he is not an extension of the Twelve. His ministry was in virgin territory, while the Twelve's ministry was confined within Israel's borders.

2 Corinthians 10:14

For we stretch not ourselves beyond our measure, as though we reached not unto you: for we are come as far as to you also in preaching the gospel of Christ:

What does Paul call the gospel of grace, the gospel of Christ, and the gospel of God?

Paul identifies the gospel of grace, the gospel of Christ, and the gospel of God as “my gospel.” This message stands in contrast to the gospel of the Kingdom, which Jesus and the Twelve proclaimed to the nation of Israel.