That isn't as easy as you think...
First, AIs are scripts and in no way they make an entity show emotions (in FPSC). FPSC is very limited in its scripting language and makes that nearly impossible. Ask someone to make it.
Second, to make the tank shoot, or even hit enemies, will be too complicated. You can make it follow waypoints. Just give it this script:
;Artificial Intelligence Script
;Header
desc = Follow Waypoints
;Triggers
:waypointstate=0:waypointstart
:waypointstate=3:waypointnext
:waypointstate=4:waypointrandom
:waypointstate=5:waypointreverse
;End of Script
Hope that helped
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