Creeping Death
ifenemy 3         basic infection loop   (1)
go 5
infect
go 1
ifenemy 1         spin looking for something to infect  (5)
left
ifenemy 1
left
ifenemy 1
left
ifenemy 1
ifsame 34  xxx        spin looking for your own species to clump (12)
left
ifenemy 1
ifsame 34  xxx
left
ifenemy 1
ifsame 34  xxx
left
ifenemy 1
ifsame 34  xxx RANDOM:r this is the randomizer creature (21)
ifenemy 1
ifwall 29  r+8   
ifrandom 27   r+6
left
go 21  r
hop
go 21  r
left           about face routine when hit wall
ifenemy 1
ifsame 34   L
left
go 21
ifenemy 1      LAND MINE:L  (34)
ifempty 38  L+4
left
go 34
infect
ifrandom 34
ifrandom 34
ifrandom 34
ifrandom 34
ifrandom 34
ifrandom 34
go 1  every once in a while, the land mine regresses


Creeping Death -- Nick Parlante, 1991
The idea is to combine the advantages of the rover and the land mine.
Use roving behavior to get food and to find other Creeping Deaths.
Then try to clump together and face outward.