Same-Time Risk is dramatically different from Classic Risk. If you’re not familiar with it, I completely recommend playing practice games outside of the tournament before attempting this level. You also may wish to read the Same-Time Risk portions of the strategy guide in my website.
I like to start same-time risk with North America; it is not too hard to defend and provides a fair amount of extra reinforcements.
At the beginning of the game, try to make alliances until you have conquered your continent. Forget about foreign invasions until you are safe domestically.
Contrary to regular risk, I find it best to play Same-Time Risk aggressively because the attacker – not the defender – wins the tie. In other words, it’s better to be attacking than defending.
Once I conquer North America, I start seeping outwards into Asia, Europe, South America, and even Australia. I don’t really have any strategy except “attack as much as possible.”
When I place reinforcements, I place them in my border countries first. If I max out their capacities, I put my extra troops in countries behind border countries that I fear might be taken over by my next turn.
I start to overextend myself at one point – I don’t have enough troops to do everything I want to do, so both yellow and black make it into North America. When something like this happens, the best thing to do is to forget about EVERYTHNG except your most important continent. In this case, I put as many troops as I can into North America before considering reinforcing my territories in Europe and Asia and Australia.
I regain control of North America and soon win the game. Victory.