Bohemian counter?

So I just played as Malians against an all Bohemian play on Arabia. When I saw Hussite wagons I went fast imp and got onagers out. Even had a castle drop on my base and was able to hold off. It is expensive but onager can kill/damage the wagons quickly. Two to three shots and you can reduce the mass in half or more.

I remembering hearing mango/onager is the the technical counter to the wagons but have seen it fail. Was just curious if any others have had luck countering Bohemians and what the strat was.

I should note the player didn’t have monks so my onagers were more effective.