There were, of course, two Dark Shadows games and the first adverts below are for the original board game simply entitled
Dark Shadows Game which was available from Lane's Discount Drug Store $1.33. A modest price for a strategy board game which would have also bought you nearly 8 toothbrushes, 2 swinger purses, 13 flashlight batteries and 3/4 of a box of Velvo Perfecto Cigars.
from The Toledo Blade, April 9, 1970
The rest of the adverts are from 1970-71and feature the second game entitled
Barnabas Collins Dark Shadows Game. In this version the task was to build a skeleton from the glow-in-the-dark skull and bones, determined by a wheel spin. The skill level was obviously geared towards a younger audience.
from The Derrick, October 29, 1970
Other popular games of the time were Your America, Karate Tops (a kin to Spinning Tops), Plug-A-Jug, Mind Maze, Don't Cook Your Goose, Snoopy and the Red Baron, Hang On, Harvey!, and the eternal classic, Monopoly.
from The Milwaukee Journal, December 9, 1970
Another ad featuring Dark Shadows, Plunk and Battling Tops.
from The Mount Airy News, November 27, 1970
And a Christmas season ad from Sears featuring Super Bowl Electric Football, Proffesional Hockey Game (bubble hockey minus the bubble), Big Action Karate Robot among other classics. The Sears Ted Williams 125-lb. Bar Set could also be had for a mere $24.99.
from The Reading Eagle, December 9, 1970
With the end of the television show in 1971 came the liquidation of the board game for $2.00. Hang On Harvey, Buck-A-Roo, Marble Head, Swords and Shields, Chips Are Down, Design Machine, Spirofoil and Go To Head Of Class were also in the bargain bin and priced to move. I believe that this was from a Kroger several page ad.
from The Lawrence Journal-World, November 30, 1971
Dark Shadows itself was a catalyst in reviving interest in the occult and supernatural which was evidenced in the influx of board games of that nature in 1970. Titles such as Witch Pitch, Which Witch, Mystery Zodiac Game and the aforementioned Barnabas Collins game were featured prominently at the American Toy Fair that year. Apparently, not only were kids interested in the games but parents were willing to buy them.
from The New York Times, March 8, 1970
Lastly, here's a television commercial for the Barnabas Collins game:
and a groovy demonstration of the game by a vampy chick with Eddie Munster shaped bangs: