game that two can play, that's a - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Also, two can play at that game. Another can behave in the same way or do the same thing. For example, He refused to tell us whether he would go or stay, but that's a game two can play. This expression is generally used as a threat of retaliation. [Early 1800s]