that makes two of us—
1. is used to say that one is in the same position:
- She wanted reassurance. That makes two of us, he thought.
2. is used to indicate agreement with what another speaker just said:
- “I find the Church’s stance in this case absolutely revolting.” “That makes two of us, Chris.”
Cf.: that makes one of us—my opinion is different from yours here (used as a pun on the former):
- “Liz, I’m really glad you decided to come here,” I said. She gave a short laugh. “So far that makes one of us.”
two can play at that game—is used to say that one can act in a similar objectionable way (as retaliation for smb.’s unfair practices):
- Sulking until you get your own way is a game that two can play, you know.
Note: The expression does not correlate in meaning with the phrase it is a game of two halves—used to say that smb.’s fortunes or luck in sports, etc. may change:
- The history of British Liberals is a game of two halves. Up to 1914, they enjoyed the moral ascendancy in politics.
See also: it takes two to make a bargain / it takes two to tango.