On Sunday, my brother and I played two games of eighth edition Warhammer 40,000 using just the miniatures in the Dark Imperium core box. To keep things simple, we played Open War (the big what you have/want).
Our first game was Annihilation, in which we setup 24 inches apart, with the goal to have the last models on the table. The game was very much about getting a handle on the rules for the game and two forces. My brother forgot that Nurgle Resiliency was an army-wide benefit for him for the first two turns, in which I did significant damage to the bulk of his army.
For the second game, we played Hold at All Cost. I dropped two of my units to be the smaller force attempting to hold the center of the table. My lack of heavy firepower resulted in my army being destroyed by the top of turn 5. A few lucky rolls in there and I may have been able to pull off a victory, but to no avail.