From news-rocq.inria.fr!univ-lyon1.fr!jussieu.fr!math.ohio-state.edu!usc!elroy.jpl.nasa.gov!jlayland Tue May 10 13:14:52 1994 Article: 777 of rec.games.corewar Path: news-rocq.inria.fr!univ-lyon1.fr!jussieu.fr!math.ohio-state.edu!usc!elroy.jpl.nasa.gov!jlayland From: jlayland@kilroy.jpl.nasa.gov (James Layland) Newsgroups: rec.games.corewar Subject: Request and antivamps (was Re: Pyramid v2.0) Date: 9 May 1994 23:12:18 GMT Organization: Jet Propulsion Laboratory, Pasadena, CA USA Lines: 38 Message-ID: <2qmg0i$1ko@elroy.jpl.nasa.gov> References: <2qf1d8$1s4@agate.berkeley.edu> NNTP-Posting-Host: 128.149.63.2 In article <2qf1d8$1s4@agate.berkeley.edu>, Michael Constant wrote: >quick-scanners.) Why, you may ask, do I use a standard vampire when I >could use a non-standard one like Request which is not vulnerable to anti- >vamps? Well, it's because of the quick-scan. All modern anti-vamps are >either packaged with, or incorporated into, some sort of paper. (The reason >for this is that the anti-vamp will destroy either the pit or the fangsource >(depending on the type of anti-vamp) but this will usually leave the vampire >intact -- acting as a stone. The purpose of the paper is to beat that Request is invulnerable to _some_ anti-vamps. Request bombs with fangs like JMP @xx, yy. xx points to a DAT statement, which points to the pit. An antivamp which tries to kill the pit by bombing through xx will only kill the pointer (leaving any processes already trapped in the pit). Request has a small routine which occasionally refreshes the pointer in case it has been destroyed. However, any anti-vamp which bombs the fang source (tracing back through yy) will still work. This effectively turns the vamp into a stone, which can be defeated by paper. If the vamp has already caught something, the processes stay trapped and a tie is likely. For example, this paper will beat Request about 70% of the time. spl 1 spl 1 spl 1 start mov #8, 0 copy mov <-1, 100 ; now bomb forward to kill jump mov bomb,>avamp jmz start, start bomb dat <2667, <2*2667 ; might take out an imp if I'm lucky -- James Layland jlayland@grissom.jpl.nasa.gov