Players may make informal agreements (e.g., “I won’t attack you this turn if you don’t attack me next turn”). The only tangible items that may be exchanged are coins. In tournament play, coins may not be exchanged for deals or alliances.
You can’t negotiate your way out of a combat that has already begun—that is, if a player moves their character and/or mechs onto a territory you control with your character and/ or mechs, at the end of their Move action, the two of you must engage in combat (you can’t pay them off at that point, though you could try to influence the outcome). Agreements made between players are not enforceable.