You are looking at many t-bomb nots

if reacting to arrives then doit else end;

##doit:
runsub starttimer;

##starttimer:
print "[$actor] begins ticking madly!";

//to set the bomb, remove the 'x' in 'xtickloc'

##xtickloc:
runsub ticked;
##ticked:
set $counter = 45;
print "[$actor] ticks loudly; [$counter] seconds left!";
take 1 from $counter;
if $counter < 1 then blowup else end;
##blowup:
foreach in $loc do checkif;
##checkif:
if $for_id's material like '_living_' then finishup else end;
##finishup:
$hlth = $for_id's health;
$hlthm = $for_id's healthmax;
take 8 from $hlth;
if $hlth < 1 then killit else continue;

##killit:
set $for_id's health = 0;
print "[$for_id] is obliterated!";
call "erase $actor";

##continue:
set $for_id's health = $hlth;
print "[$actor] explodes, sending out a massive shockwave!";
$what = (is flung against the wall, is slammed to the ground, is pelted with shrapnel, is torched by flames);
print "[$for_id] $what!";
call "erase $actor";