Is this cheating? [sorted]

[1Way2God]

In a 3 player game can 2 players form an alliance to kill the 3rd player?

In a 3 team game can 2 teams form an alliance to kill the 3rd team?

[king achilles]

Any form of collusion between opponents must be announced beforehand in the game chat, in English or in a language all players understand.

So, if this done, then it is not cheating.

To have a more understanding about the rules, you can check them at:
http://www.conquerclub.com/public.php?mode=rules