The "Better Off Dead" achievement can be completed if you get a streak of 10 in "I, Zombie Endless". I understand that much.
This mode is really hard and I cannot get my streak near 10 games in a row, although I cannot put my finger on my main mistakes. I am happy if I can win 7 in a row. Are there any common tactics I can apply to improve my game or are there any common mistakes I should avoid? For example I have no idea if it is always best to send single zombies, or if I should combine more than one zombie in some situations.
While searching the Internet for guides I found someone claiming that the use of the "Lead Dancer" Zombie is often key - a Zombie type I usually don't like to use. Under which circumstances is it good concerning cost and value?