How to win 3v1 vs noobs no cards

Every 6 months, me and 3 friends cram into an internet cafe to play our 6 monthly game of ffa aoe3

Every time, all 3 will team up on me (I always have the best score), and will wear me down to defeat

Occasionally I'm able to lay massive blows to my enemies economies, but the other 2 will attack me before I can strike the killing blow, forcing me to stay back and defend while the guy I attacked rebuilds his eco.

We never have cards in these games, and only play the original game (no expansions)

This has gone on for 3 years straight, How do I win these?