Change the type of member variables in InitGameEvent due to prevent use the null pointer.
Change the return type of ArchitectureMarket::cards() because we won't use the Card (especially operate the card's effect) when call ArchitectureMarket::cards().
InitGameEvent
due to prevent use the null pointer.ArchitectureMarket::cards()
because we won't use the Card (especially operate the card's effect) when callArchitectureMarket::cards()
.