Terminate the commander? is this an assasination thing, you hunt someone who is protected and kill them ?

Defend the monument? That is the game on multiplayer on the demo yes?

Commander of the base? How does this differ from the above?

Ok, we start with terminate the commander. Kill the commander. It's like regicide. Defend the monument is when one person has a wonder and must protect it for the time limit. Commander of the base is when there is a base in the middle. It can switch between players like nerfs. Keep it till the time limit=victory.

ok last two are clear, kinda what I thought, but regicide? I've never played AoE I take it that is a game time in there?

yes. There is a unit called a "commander." This commander is someone you need to protect. Kill him to win, or resigning or if somethign else happens.

whats the death match option called (for those of u who dont know just think HUGE recources)