Just want to clarify that I know that stone cards have a invisible suit and rank but I feel like this isn't very obvious that this would happen given the 'no rank or suit' part.
On a slightly different note, wild cards still work with blackboard.
#Blackboard doesn't trigger if you have a stone card that was originally red suit
broken sluice
manic nacelle
Any stone card should not work with blackboard
or atleast they use to not to
and wild cards should work with blackboard, so that parts intended
zinc sentinel
Yeah this is intended, no stone cards work with blackboard
(i tested the stone cards that were originally black interaction recently)
median pasture
to more specifically state what Blackboard requires, all cards in hand need to have either Spade or Club as one of its suits. (Wild card has both Spade and club, Stone has no suit so neither Club nor Spade, Having no cards in hand also counts as all the cards in hand technically have Spades/Clubs) ||I can try and find an article explaining that last part if you want||