I made cusatom achiefments for all animals and npc . You must kill each to get a achiefment. But there is a time limit.
The "kill_time" on the sidebar starts by 960sec(16min.) and counts down. Every time you get a achiefment from the list
"i get it all", the time will reset. When it runs out, the timer "over_time" will start by 960sec. When "over-time" runs out
you loos the map. By getting the next achiefment, "over_time" would stop, and the "kill_time" will restart.
You winn the map when you get all achiefments from "i get it all" before the "over_time" runs out.