Not to put you down but beating this game with 5 people in one base isn't that hard.
Ok, do it without stalling creeps so that weak ones are hitting your walls and post that up with only 1-3 people and post up the replay. Nightmare mode ofc. 2 snipers max.
Doing it via killing everything as soon as it reaches the walls is actually exceedingly difficult. Add in the fact we used a 6 wall base, which requires a minimum of 12 repair bots, 6 (i use 8) engineers, the costs are absolutely huge. (as an example, light walls + maxed without robotics engineers and bots = 12+60+150+300+600+1200, +16+80+160+240+8 gold + 72 + 144 + 240 + 360 + 12 gold.
3634 lumber. This may not sound like very much, but the walls will barely survive at ~30 mins remaining and to get 3600 lumber that you can spend will need roughly double that in production. So 7200 lumber produced in 20 mins? Whilst surviving that 20 mins anyway?
Doesn't really matter how it's done, any completion of nightmare is an achievement. Air is next on my list to conquer
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Thanks for response about sniper and items niwa