diff --git a/lib/tasks/characters.rake b/lib/tasks/characters.rake
index 81a6781..97a64f9 100644
--- a/lib/tasks/characters.rake
+++ b/lib/tasks/characters.rake
@@ -3,6 +3,108 @@
 require 'csv'
 
 namespace :characters do
+  # Known character lists for series detection
+  ETERNALS = %w[Seofon Tweyen Threo Feower Fif Seox Niyon Eahta Tien Anre].freeze
+  EVOKERS = %w[Maria\ Theresa Caim Lobelia Alanaan Fraux Katzelia Haaselia Nier Estarriola Geisenborger].freeze
+  ZODIACS = %w[Anila Andira Mahira Vajra Kumbhira Vikala Catura Cidala].freeze
+
+  # Infer season from name suffix
+  def self.infer_season(name)
+    return GranblueEnums::CHARACTER_SEASONS[:Valentine] if name.include?('(Valentine)')
+    return GranblueEnums::CHARACTER_SEASONS[:Summer] if name.include?('(Summer)') || name.include?('(Yukata)')
+    return GranblueEnums::CHARACTER_SEASONS[:Formal] if name.include?('(Formal)')
+    return GranblueEnums::CHARACTER_SEASONS[:Halloween] if name.include?('(Halloween)')
+    return GranblueEnums::CHARACTER_SEASONS[:Holiday] if name.include?('(Holiday)')
+
+    nil # Standard characters have nil season
+  end
+
+  # Infer series from name and known lists
+  def self.infer_series(name)
+    series = []
+
+    # Check name suffix patterns first
+    if name.include?('(Grand)')
+      series << GranblueEnums::CHARACTER_SERIES[:Grand]
+    elsif name.include?('(Event)')
+      series << GranblueEnums::CHARACTER_SERIES[:Event]
+    elsif name.include?('(Promo)')
+      series << GranblueEnums::CHARACTER_SERIES[:Promo]
+    elsif name.include?('(Collab)')
+      series << GranblueEnums::CHARACTER_SERIES[:Collab]
+    end
+
+    # Check seasonal series (can combine with above)
+    series << GranblueEnums::CHARACTER_SERIES[:Summer] if name.include?('(Summer)')
+    series << GranblueEnums::CHARACTER_SERIES[:Yukata] if name.include?('(Yukata)')
+    series << GranblueEnums::CHARACTER_SERIES[:Valentine] if name.include?('(Valentine)')
+    series << GranblueEnums::CHARACTER_SERIES[:Halloween] if name.include?('(Halloween)')
+    series << GranblueEnums::CHARACTER_SERIES[:Formal] if name.include?('(Formal)')
+
+    # Check known character lists (base name without suffix)
+    base_name = name.gsub(/\s*\([^)]+\)/, '').strip
+
+    if ETERNALS.any? { |e| base_name == e }
+      series << GranblueEnums::CHARACTER_SERIES[:Eternal]
+    end
+
+    if EVOKERS.any? { |e| base_name == e }
+      series << GranblueEnums::CHARACTER_SERIES[:Evoker]
+    end
+
+    if ZODIACS.any? { |z| base_name == z }
+      series << GranblueEnums::CHARACTER_SERIES[:Zodiac]
+    end
+
+    # Default to Standard if no series detected and not a special type
+    series << GranblueEnums::CHARACTER_SERIES[:Standard] if series.empty?
+
+    series.uniq
+  end
+
+  # Infer gacha_available from series
+  def self.infer_gacha_available(series)
+    non_gachable = [
+      GranblueEnums::CHARACTER_SERIES[:Eternal],
+      GranblueEnums::CHARACTER_SERIES[:Evoker],
+      GranblueEnums::CHARACTER_SERIES[:Event],
+      GranblueEnums::CHARACTER_SERIES[:Collab],
+      GranblueEnums::CHARACTER_SERIES[:Promo]
+    ]
+
+    # If any series is non-gachable, the character is not gachable
+    (series & non_gachable).empty?
+  end
+
+  desc 'Auto-populate season/series from character names'
+  task auto_populate: :environment do
+    test_mode = ENV['TEST'] == 'true'
+    updated = 0
+    skipped = 0
+
+    Character.find_each do |character|
+      season = infer_season(character.name_en)
+      series = infer_series(character.name_en)
+      gacha_available = infer_gacha_available(series)
+
+      if test_mode
+        puts "#{character.name_en}:"
+        puts "  season: #{season} (#{GranblueEnums::CHARACTER_SEASONS.key(season)})"
+        puts "  series: #{series} (#{series.map { |s| GranblueEnums::CHARACTER_SERIES.key(s) }.join(', ')})"
+        puts "  gacha_available: #{gacha_available}"
+        updated += 1
+      else
+        if character.update(season: season, series: series, gacha_available: gacha_available)
+          updated += 1
+        else
+          puts "Failed to update #{character.name_en}: #{character.errors.full_messages.join(', ')}"
+        end
+      end
+    end
+
+    puts "Updated: #{updated}, Skipped: #{skipped}"
+    puts "(TEST MODE - no changes made)" if test_mode
+  end
   desc 'Export characters to CSV for season/series mapping'
   task export_for_mapping: :environment do
     output_path = ENV['OUTPUT'] || Rails.root.join('export', 'characters_for_mapping.csv')