bloodthirsty dragomancer sword

when a dragon enters the battlefield under your control control untap dragomancer sword. {t}:pay 1 life and put a blood counter on bloodthirsty dragonmancer sword and if you have 3 or more: scry 1 and draw a card if you have 4 or more bloodthirsty dragomancer sword get lifelink and if you have 6 or more: sacrifice bloodthirsty dragomancer sword and put a dragon of your deck on the battlefield