Let us say your deck contains one Vendilion Clique in main deck and an additional Vendilion Clique in the sideboard. If you own one Vendilion Clique both will show up as cards you own, indicating you have the cards available.

Could you implement it so that it shows up in red both places if you don't own the sum of Vendilion Clique in maindeck plus sideboard?

Alternatively, could you mark the maindeck as owned and use the sum for the sideboard? So the Vendilion Clique in maindeck would be a card you own while the one in the sideboard is a card you're missing.

When this came up before I got the impression that it would not be fixed until the long-awaited tagging system is implemented. Since it looks like tagging will be a premium feature this may never be fixed for free users.

torgeir wrote:Let us say your deck contains one Vendilion Clique in main deck and an additional Vendilion Clique in the sideboard. If you own one Vendilion Clique both will show up as cards you own, indicating you have the cards available.

Could you implement it so that it shows up in red both places if you don't own the sum of Vendilion Clique in maindeck plus sideboard?

Yep, this is a bug. Added to the todo list.