Passive tames require a feeding interval every x seconds or minutes. A mantis for example requires 1 deathworm horn every 3 minutes, having a timer which gives a alarm every 3 minutes so you know when to feed it again, would be perfect. The feature should be a bit like this website which i'm using now: http://www.online-stopwatch.com/loop-countdown/ You set up the time you want to make a alarm for, and the ammounts of loops it has to make (from 1 to infinite). Everytime when it makes a sound, you know when to feed it (make the sound slightly different than the default narcotic wakeup timer)