diff --git a/day15.cr b/day15.cr
index 8433f14..c89cf38 100644
--- a/day15.cr
+++ b/day15.cr
@@ -213,9 +213,10 @@ end
 def step(map, units)
   sort_reading_order(units)
   index = 0
+  elf_death_count = 0
   while index < units.size
-    return true if (units.count &.[:type].==(:elf)) == 0
-    return true if (units.count &.[:type].==(:goblin)) == 0 
+    return nil if (units.count &.[:type].==(:elf)) == 0
+    return nil if (units.count &.[:type].==(:goblin)) == 0 
 
     unit = units[index]
     unit = moved_unit(map, units, unit)
@@ -224,6 +225,7 @@ def step(map, units)
     if attacked_u
       attacked_index, attacked_unit = attacked_u
       if attacked_unit[:hp] <= 0
+        elf_death_count += 1 if attacked_unit[:type] == :elf
         units.delete_at attacked_index
         index -= 1 if index >= attacked_index
       else
@@ -233,7 +235,7 @@ def step(map, units)
     index += 1
   end
 
-  return false
+  return elf_death_count
 end
 
 def check_win(units)
@@ -252,16 +254,29 @@ def winning_score(units, type)
   units.select(&.[:type].==(type)).sum &.[:hp]
 end
 
-simulating_units = units.dup
-steps = 0
-# draw(map, simulating_units)
-until won = check_win(simulating_units)
-  steps += 1 unless step(map, simulating_units)
+power = 3
+loop do
+  simulating_units = units.dup.map do |unit|
+    next unit unless unit[:type] == :elf
+    { x: unit[:x], y: unit[:y], hp: unit[:hp], type: :elf, power: power }
+  end
+  steps = 0
+  died = false
   # draw(map, simulating_units)
-  sort_reading_order(simulating_units)
-  # simulating_units.each do |unit|
-  #   puts "health (#{unit[:type]}): #{unit[:hp]}"
-  # end
-  # puts "-- (end of roun #{steps})"
+  until won = check_win(simulating_units) || died
+    result = step(map, simulating_units)
+    if result
+      steps += 1 
+      died = result > 0
+    end
+    # draw(map, simulating_units)
+    sort_reading_order(simulating_units)
+    # simulating_units.each do |unit|
+    #   puts "health (#{unit[:type]}): #{unit[:hp]}"
+    # end
+    # puts "-- (end of roun #{steps})"
+  end
+  puts "(power: #{power}) #{steps} * #{winning_score(simulating_units, won)} = #{steps * winning_score(simulating_units, won)}"
+  break if !died && won != :goblin
+  power += 1
 end
-puts "#{steps} * #{winning_score(simulating_units, won)} = #{steps * winning_score(simulating_units, won)}"