DOA5 Last Round and Halloween Costume Set bundle is available during Halloween Sale period.
This bundle is limited time offer with 77% discount now!
http://store.steampowered.com/bundle/1773/
Also, Halloween themed DLCs are being offered with 60% discount.
http://store.steampowered.com/app/358141/
http://store.steampowered.com/app/403350/
http://store.steampowered.com/app/403061/