My opponent cast Insatiable Avarice on me and adds the second spree-funktion, draw three cards and lose 3 life. I have 2 life left so this will kill me. I'm trying to sacrifice a food before this sorcery resolves but I can't. Sacrificing food is instant speed. I can tap my mana, and I have more than enough to pay for the food (2), but I can't interact with my food. The result is that I die from Insatiable Avarice when I should be able to have sacrificed a food, gain 3 life and survive.