Easy Unstoppable Combo

 Hello ladies and Gents, this is Tom Bree speaking and I'd like to tell you of yet another easy unstoppable combo, here it goes.
 
    First off I'd like to say that no one ever specified if it was legal or illegal to change a monster's attribute once they were in the
graveyard. So with that in mind let me continue.
 
    Ok, this combo is composed of 1 Zombie monster on the field, one powerful monster in your graveyard (that can be special
summoned), and two magic cards, Scroll of Bewitchment and Book of Life. Now that I have stated the cards let me tell you of
their abilities.
 
Scroll of Bewitchment, Labriyth of Nightmare
Select one attribute when you activate this card. Change the attribute of the equipped monster to the one you select.
 
 
 
 
Book of Life, Pharonic Guardian
Special Summon one zombie type monster from the graveyard in face up attack or defense position and remove one
monster in your opponents graveyard from play.
 
When you have all these cards in your hand and on the field, you should begin by setting Scroll of Bewitchment face
down on the field and then set Book of Life down on the field also.
    After doing so equip Scroll of Bewitchment to your zombie monster and whatever powerful monster card you have
in your graveyard change it's attribute to a zombie.
    Now this is where it becomes somewhat controversial, some opponents will say that changing a monster's attribute
that already inhabits the graveyard is illegal.
    If your opponent agrees to this move then flip your Book of Life over and Summon that Powerful Monster from your
graveyard and go to it.
 
                    Hope you liked my tip
                    Tom Bree