In 30% of all games, humans are complete idiots, they camp in their base until a tie or a loss.
This tactic results in a loss two-thirds of the time.
Now, take that 50% Alien, 30% Human, 20% tie game statistic and ignore camp ground games.
You get 30% Alien, 30% Human, 10% tie, with 30% Discarded.
Uncreation, you start with 40% Alien, 40% Human, 20% tie game and you end up with 20% Alien, 40% Human, 10% tie, 30% Discarded
Yes, Uncreation is balanced if the teams are comprised of average demographics.
However, if both teams know what they are doing, then the Aliens know that they are screwed.