Gozuki is quite versatile in a zombie deck, especially when you run multiple copies of him. He can be use to send zombie-type monsters from deck to the graveyard where they can easily be revived or, if you have a zombie-type monster in your graveyard that isn't Gozuki, you can send another Gozuki to the graveyard to activate his effect and special summon a zombie-type monster from your hand. Both of Gozuki's effects will help you get Red-Eyes Zombie Dragon out on the field. Goblin Zombie will primarily be used to search Gozuki, but can also be used to search another Goblin Zombie to mill down your deck. Red-Eyes Insight searches for Red-Eyes Spirit and sends Red-Eyes Zombie Dragon to the graveyard, making it practically a free Red-Eyes Zombie Dragon summon when you revive him with the Red-Eyes Spirit you added to hand.
Red-Eyes Zombie Dragon and is basically a 2400 attack beatstick, but unlike other beatsticks with similar or more attack, Red-Eyes Zombie Dragon is very well supported belonging to at least two archtypes, namely zombies and red-eyes. Because of this, there are many ways in which he can be summoned. You can special summon him form your hand with the effect of Gozuki, or revive him from the grave with Red-Eyes Wyvern or Red-Eyes Spirit. You can also tribute summon him with one zombie-type monster, if summoned this way using Gozuki as tribute will allow you to use Gozuki's effect to special summon another zombie-type monster from your hand, or by using Goblin Zombie as tribute for tribute summoning allows you to search your deck.
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