Bought a few games on steam that are/were discounted and felt perfectly "Halloweenie" for the season.
Couple Dracula-based Castlevania-styled games:
https://store.steampowered.com/app/1189 ... f_Dracula/
https://store.steampowered.com/app/1794 ... 1_Manhunt/
Couple Sherlock Holmes-based games:
https://store.steampowered.com/app/2412 ... nishments/
https://store.steampowered.com/app/3506 ... _Daughter/
And one flappy bird clone only with a bat and themed for Halloween:
https://store.steampowered.com/app/2159 ... ppy_Bat_2/
Haven't played any yet, but they were on sale for pretty cheap and I wanted something to play to fit the season, so hopefully they'll fit.