Vampire

var TARGET_ARRANGEMENT_RAIL = [
    [3,5,6,1,6,7,6,2,8],
    [3,5,6,4,6,7,6,2,8],
    [1,6,7,6,2,8,3,5,6],
    [4,6,7,6,2,8,3,5,6],
    [6,2,8,3,5,6,1,6,7],
    [6,2,8,3,5,6,4,6,7]
];
var TARGET_COLOURS_RAIL = colour_band([6, 5, 2]);
var rail_miners = {
  likely_nest: function(colours) {
    var bestScore = 0;
    TARGET_ARRANGEMENT_RAIL.forEach(function (arrangement) {
        ROTATIONS.forEach(function (rot){
            var score = 0;
            for(var i = 0; i < 9; i++) {
                score += arrangement[i] == view[rot[i]].color?1:0;
            }
            if(score > bestScore) {
                bestScore = score;
            }
        });
    });
    if(bestScore >= 6) {
        return true;
    }

    return false;
  },

  likely_victim: function(victim_pos) {
    var c0 = TARGET_COLOURS_RAIL.next(WHITE);
    var c1 = TARGET_COLOURS_RAIL.next(c0);
    if(view[victim_pos].color !== c0) {
      return false;
    }
    for(var i = 0; i < 9; ++ i) {
      if(i !== victim_pos && near(i, victim_pos) && view[i].color === c1) {
        return true;
      }
    }
    return false;
  },

  follow_victim: function(me, buddies, colours, victim_pos) {
    if(me.type === THIEF && !buddies[QUEEN]) {
      // Queen may be on other side of victim; try orbiting to find her
      return try_all_angles([
        (rot) => ((victim_pos === rot[1]) ? {cell: rot[0]} : null),
        (rot) => ((victim_pos === rot[0]) ? {cell: rot[3]} : null)
      ]);
    }

    if(me.type === QUEEN && !buddies[THIEF] && me.food > 0) {
      // Make a buddy to help us steal
      return best_of([
        try_all_cells((i) => (near(i, victim_pos) ? {cell: i, type: THIEF} : null), true),
        try_all_cells((i) => ({cell: i, type: THIEF}), true)
      ]);
    }

    return best_of([
      // Ziggurat will try to drown us in workers; make sure we have plenty
      // of our own (but only if it's worth it)
      (view[victim_pos].ant.food > 4) &&
        try_all_cells((i) => (near(i, victim_pos) ? {cell: i, type: THIEF} : null), true),

      // Continue to steal and get fat
      NOP
    ]);
  },

  find_victim: function(me, buddies, colours) {
    var current = view[CENTRE].color;

    // Easier to navigate alone, and thief reaching queen first would be a
    // disaster, so the thief just gives up.
    if(me.type === THIEF) {
      return go_anywhere;
    }

    var target = colour_band_prev(TARGET_COLOURS_RAIL, current);
    var antitarget = colour_band_prev(TARGET_COLOURS_RAIL, target);
    var ret = best_of([
      try_all_cells((i) => ((i % 2 == 1 && view[i].color == target && view[8-i].color == antitarget) ? {cell: i} : null)),
      //try_all_cells((i) => ((view[i].color == current) ? {cell: i} : null)),

      // Random walk to avoid getting stuck
      {cell:4}
    ]);

    if(ret == null || ret.cell == 4) {
      var numAnts = 0;
      for(var na = 0; na < 9; na++) {
        if(view[na].ant != null) numAnts++;
      }
      if(numAnts == 1) ret = go_anywhere;
    }
    return ret;
  }
};