Preventing game over

Guys.
"The Red Wizardess minion has tapped Eloran Oasis and cast dominion spell."
"The Red Wizardess have attained dominion over Shanalar."
Unfortunately I have a saved the game virtually moments before this happens. So now I must start a new game.
I have no clue what I should be doing to prevent this. My black or black green deck can probably handle most enemies (at least with savescumming.) Any idea what I can do in future to make sure a game over doesn't happen?
Is there any way to monitor who\what needs to be defeated to prevent game over?
That said i have an older save, where I probably have enough time to run across the entire map and fight who i need to fight.
"The Red Wizardess minion has tapped Eloran Oasis and cast dominion spell."
"The Red Wizardess have attained dominion over Shanalar."
Unfortunately I have a saved the game virtually moments before this happens. So now I must start a new game.
I have no clue what I should be doing to prevent this. My black or black green deck can probably handle most enemies (at least with savescumming.) Any idea what I can do in future to make sure a game over doesn't happen?
Is there any way to monitor who\what needs to be defeated to prevent game over?
That said i have an older save, where I probably have enough time to run across the entire map and fight who i need to fight.