While the -9 ability threatens to tutor every dragon from your library and put them into play all at once, Sarkans expensive to cast and its other abilities are pretty weak
This essentially halves the use that players have of their lands, in turn causing the game to move at half-speed for each player besides Vorinclex's controller.
The Rakdos enchantment steals a card off an opponent's deck and punishes them with life loss when you cast it, talk about nasty
Once you do, both of them have an ability that triggers
Its almost always a two-for-one at the very least, and potentially game-winning if you reach the final chapter
Before youre forced to discard, you can cast these spells at instant speed and trigger the drain effect multiple times, rebuilding your life total after paying so much for your Necro effect