Start of the game :
- If both player have this card, destroy them and each turn only lasts for 15sec
- If only 1 player have this card, shuffle 5 random legendary into your deck .
The idea is bad and already taken but the point is to have another sort of effect if only 1 player uses it . Making it a hard choice to include or not(you either get its powerful 1 player only effect or you get put into blitz mode)