If you click on the lock in the top left (of chrome at least), you can actually reenable flash assuming you previously had it and continue playing like normal (although offline) - hope this helps someone
More Levels - Variety In Levels (Background) - Longer A Unit Survives, It Can Level Up And Gain More Damage And Health (Farmers) - Ability To Upgrade Production Rate Further In Later Levels As This Is The Main Choke Point And Almost Makes The Last Level Uneatable Without The Right Strat
 "Swarm Simulator"){kind=icon}
 "Learn to Fly 3"){kind=icon}
 "Zombie Trailer Park"){kind=icon}