The texas legislature can override the governor's general veto with a vote in each house.

With a 2/3 vote. If both the Texas Senate and the Texas House get two thirds of votes to override, they can override a veto and nobody can do anything about it. It's similar even in the congress of the federation, not just a Texas thing. This is called a large majority and it's that many people because it's usually about serious things that can't just be decided easily.