Rank gain related info
you can go into a base, die as many times as you want perfecting the run. then you can quit the map, come back in, do it in 1 run, and get full rank. you can now receive your rewards for beating a challenging outpost instead of just getting 0. Perfect your run, then leave and refresh your death counter for full rank. this will reward the builders with your deaths, you with practice in harder outposts, and you again with full rank reward on completion for beating something hard.
have fun lovelies.