As a gag the other day on a MUD I frequent, I thought I'd have a look and see if I could get myself out of a fight by trying to rescue my attacker. This did not go so well... It worked, but I can safely say that I took too long to realize I was kicking my ass.

This presents two problems, one which I have the fix for.

In skills.c, in function do_rescue(), find the following:

   if( ( fch = who_fighting( victim ) ) == NULL )
   {
      send_to_char( "They are not fighting right now.\r\n", ch );
      return;
   }

   ch->alignment = ch->alignment + 5;
   ch->alignment = URANGE( -1000, ch->alignment, 1000 );

Directly BEFORE that, add the following:

   if( ( fch = who_fighting( victim ) ) == ch )
   {
	   send_to_char( "One would imagine THEY don't need your help.\r\n", ch );
	   return;
   }

The second problem is... Why are multi_hit and one_hit allowing ch == victim? That makes no sense. I'm not sure about set_fighting... I don't think it should allow ch == victim, but I'm not absolutely sure about it. Damage should probably be the only such function that allows ch == victim... You shouldn't be able to carry a round of combat against yourself. That just seems absurd to me.

Smaugfuss luckly already has a check in do_rescue for victim == ch and who_fighting( victim ) == ch.
From the looks of it, the others you mentioned probably would allow ch == victim lol.
I'll just let samson fiqure out the best possible fix for them lol, personaly I'd go with in each part that I thought shouldn't allow it having a check to protect it.