The Legendary Dragons

Timaeus, Critias and Hermos- The Legendary Dragons- featured in Yugioh Season 4 (Though I consider it Season 3. I refuse to count Battle City and Battle City Finals as separate Seasons) Waking the Dragons.

As most players know, Yugi'/Pharaoh's Dragon Timaeus was released in the game, but Critias and Hermos, Kaiba's and Joey's Dragons respectively, were never printed... until now.

The Eye of Timaeus

(This card is also always treated as "Legendary Dragon Timaeus".)

Target 1 "Dark Magician" monster you control; Fusion Summon 1 Fusion Monster from your Extra Deck that lists that monster on the field as a Fusion Material Monster, using it as the Fusion Material. You can only activate 1 "The Eye of Timaeus" per turn.

So I just thought I'd get Timaeus out of the way first. It's important to note that Timaeus is the strongest of the Dragons, at least in the monsters he creates and their abilities. These are the monsters that Timaeus is used to Fusion Summon.

Additionally, "The Eye of Timaeus" doesn't have to to be used to summon these monsters. It can be used with the Dark Magician to fusion Dark Paladin or Dark Flare Knight

Amulet Dragon

"Dark Magician" + 1 Dragon-Type monster

Must be Fusion Summoned with the above Fusion Material Monsters or with "The Eye of Timaeus", and cannot be Special Summoned by other ways. If this card is Special Summoned: Target any number of Spell Cards in any Graveyard(s) (min. 1); banish those targets, and if you do, this card gains 100 ATK for each card banished by this effect. If this card is destroyed: You can target 1 Spellcaster-Type monster in your Graveyard; Special Summon that target.

Even just reading through the effect, you can see the amount of uses this card has, though the effect is slightly different to the anime's one. In the anime, Amulet Dragon gained 300 ATK for each Spell Card in Yugi's Graveyard (he had 8 in total so Amulet Dragon received an extra 2400 ATK) instead of 100 points. The last effect to summon a Spellcaster from the graveyard when it is destroyed was not used by the Pharaoh to revive his Dark Magician as he chose not to activate it.

In the game today though, a lot of spells don't wind up in the Graveyard, thanks to a majority of spells being Continuous so it could re-errated to 300 ATK without too much trouble. Again, it's assumed you would be reviving the Dark Magician, but you could revive any Spellcaster you wanted including Synchro's and Xyz's

Dark Magician Girl the Dragon Knight

"Dark Magician Girl" + 1 Dragon-Type monster

Must be Fusion Summoned with the above Fusion Material Monsters or with "The Eye of Timaeus", and cannot be Special Summoned by other ways. Once per turn, during either player's turn: You can send 1 card from your hand to the Graveyard, then target 1 face-up card on the field; destroy that target.

The Pharaoh played this card twice, in both his duels with Raphael (Raphael won the first duel, but Yugi sacrificed himself to the Seal of Orichalcos to save the Pharaoh). The card's anime effect is identical to the real effect and it's pretty straight forward: discard a card and target one face up card on the field and destroy it. That can be a monster, spell card, trap card. So it's a very powerful card. It would absolutely destroy Fire Formation decks providing you can get this out of course.

The Fang of Critias

(This card is also always treated as "Legendary Dragon Critias".)

Send, from your hand or your side of the field to the Graveyard, 1 Trap Card listed in the card text of a Fusion Monster that can only be Special Summoned with "The Fang of Critias" (if that card is Set, reveal it), then Special Summon that Fusion Monster from your Extra Deck. You can only activate 1 "The Fang of Critias" per turn.

So, Timaeus has the ability to make his monsters stronger and destructive and excellent for attacking purposes. Critias can fuse himself with trap cards, making his monsters perfect for defensive strategies. Critias was Kaiba's Dragon.

Doom Virus Dragon

Must be Special Summoned with "The Fang of Critias" by sending "Crush Card Virus" from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. If this card is Special Summoned: Check your opponent's hand, all monsters they control, and all cards they draw until the end of your opponent's 3rd turn after this effect's activation, and destroy all monsters with 1500 or more ATK.

So this card is a basically a monster version of Crush Card Virus (which lost a lot of its power with the new errata) and with 1900 ATK it's not particularly difficult to get rid off, but it could certainly ruin your opponent's field advantage. It also destroys all monsters with 1500 ATK or more in their hand and/or on the field. I put that in bold because people forget it includes those on the field.

Mirror Force Dragon

"The Fang of Critias" by sending "Mirror Force" from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. During either player's turn, when a monster you control is targeted for an attack, or by an opponent's card effect: You can destroy all cards your opponent controls.

This card is not that difficult to get rid of when you think about it. Raigeki, Dark Hole, Mirror Force, basically any card that doesn’t target will destroy it. Or if you can negate its effect. 2800 ATK so it’s a decent beater and is also perfect for defence.

Tyrant Burst Dragon

Must be Special Summoned with "The Fang of Critias" by sending "Tyrant Wing" from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. This card can attack all monsters your opponent controls once each. You can target 1 monster you control; equip this monster on the field to that target. It gains 400 ATK and DEF. The monster equipped with this card by this effect can make up to 3 attacks during each Battle Phase.

This is the strongest Critias monster of all three of his forms. 2900 ATK and you can equip him and the equipped Monster can attack 3 times, perfect for an OTK/FTK strategy.

The Claw of Hermos

(This card is also always treated as "Legendary Dragon Hermos".)

Send, from your hand or your side of the field to the Graveyard, 1 monster with the same Type as 1 Monster Type listed in the card text of a Fusion Monster that can only be Special Summoned with "The Claw of Hermos" (if that card is Set, reveal it), then Special Summon that Fusion Monster from your Extra Deck. You can only activate 1 "The Claw of Hermos" per turn.

Hermos was Joey’s Dragon and it has a unique ability. Timaeus required certain monsters on the field to be used while Critias required a certain trap card either on the field or in the hand to be used. Hermos basically requires any Warrior, Dragon or Spellcaster either on the field or in the hand, making it extremely dangerous and versatile.

Time Magic Hammer

Must be Special Summoned with "The Claw of Hermos" by sending 1 Spellcaster-Type monster from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. If this card is Special Summoned: Target 1 other monster on the field; equip this monster on the field to that target. At the start of the Damage Step, if the monster equipped with this card by this effect battles an opponent's monster: You can roll a six-sided die, note the result, and banish the opponent's monster until the Standby Phase of that many turns later.

I know Shaddolls are making great use of this card because nearly all their monsters are Spellcasters. They usually use Falco or Beast, so if you’re playing against Shaddolls, use DNA Surgery to prevent or at least delay this card’s summon because it can be very difficult to deal with. If you’re using this card I highly recommend using with Tyrant Burst Dragon equipped to the same monster as you can then banish three of your opponents monsters for a random number of turns. The effect of Time Magic Hammer also makes the equipped monster invulnerable to battles because the attacking monster will be banished before the damage step.

Goddess Bow

Must be Special Summoned with "The Claw of Hermos" by sending 1 Warrior-Type monster from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. If this card is Special Summoned: Target 1 other monster on the field; equip this monster on the field to that target. Once per Battle Phase, while this card is equipped to monster by this effect, when an opponent's card or effect resolves, negate that effect, and if you do, the equipped monster can make a second attack during this Battle Phase.

This card just makes Nekroz decks even nastier and harder to deal with. Most Nekroz monsters are warriors, which is what this card needs, so if it was equipped to something like Trishula, it stops the opponent from activating trap cards or monster effects during the Battle Phase. So it stops Mirror Force, Dimensional Prison, Magic Cylinder, Lightsworn Barrier as well as the flip effects of Ryko and Magician of Faith whose effects must activate so long as there is a target (in the case of Faith).

Rocket Hermos Cannon

Must be Special Summoned with "The Claw of Hermos" by sending 1 Warrior-Type monster from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. If this card is Special Summoned: Target 1 other monster on the field; equip this monster on the field to that target. It can make a second attack during each Battle Phase, also if it attacks a Defense Position monster, inflict piercing battle damage to your opponent.

Another card that would lethal in Nekroz decks, especially if it equipped to the same monster as Goddess Bow, because think about it. Other than destroying both Goddess Bow and this card, what options does the opponent have? They can’t destroy it with effects during battle. They can’t go into defence they’ll take piercing battle damage. So until they draw into Raigeki or Dark Hole or something like that, what else have they got? Honor Ark maybe, but Nekroz players usually have Djinns and I know one of them prevents the opponent special summoning so there’s not a lot of options if they get that combo out.

Red-Eyes Black Dragon Sword

Must be Special Summoned with "The Claw of Hermos" by sending 1 Dragon-Type monster from your hand or your side of the field to the Graveyard, and cannot be Special Summoned by other ways. If this card is Special Summoned: Target 1 other monster on the field; equip this monster on the field to that target. It gains 1000 ATK. The monster equipped with this card by this effect gains 500 ATK and DEF for each Dragon-Type monster on the field and in the Graveyards.

So this card is basically an equip version of Dark Paladin and is easier to summon as well but the monster also gets a DEF bonus as well. Additionally, the equipped monster gets an automatic 1500 ATK point boost at minimum. Perfect for use in Dragon Rulers, Dragonuity’s, basically anything that uses Dragons. It can be used against Dragon decks as well and get very high attack power. Possibly the most versatile card that Hermos makes.

The Legendary Dragon cards themselves also make their own monsters when combined with the spell card Legend of Heart to create Legendary Knight Timaeus, Critias and Hermos.

Timaeus- Cannot be Normal Summoned/Set. Must be Special Summoned with "Legend of Heart", and cannot be Special Summoned by other ways. When this card is Special Summoned: You can target 1 face-up Spell/Trap Card on the field; banish that target. When this card is targeted for an attack: You can target 1 Spell Card in your Graveyard; Set that target. The banishing effect includes field spells and Pendulum monsters in the Pendulum Zones. The targeting effect of this card includes field spells, but not Pendulum monsters as a) they are not treated as spell cards when in the graveyard and b) cannot be set in the Pendulum Zones.

Critias- Cannot be Normal Summoned/Set. Must be Special Summoned with "Legend of Heart", and cannot be Special Summoned by other ways. When this card is Special Summoned: You can target 1 face-up Spell/Trap Card on the field; banish that target. When this card is targeted for an attack: You can target 1 Trap Card in your Graveyard; Set that target. That Set card can be activated during this turn. Like Timaeus, the banishing effect includes field spells and Pendulum monsters in the Pendulum Zones. Very nasty to deal with your opponent (if they’re the ones running it) can activate traps like Mirror Force or Dimensional Prison from the graveyard essentially.

Hermos- Cannot be Normal Summoned/Set. Must be Special Summoned with "Legend of Heart", and cannot be Special Summoned by other ways. When this card is Special Summoned: You can target 1 face-up Spell/Trap Card on the field; banish that target. Once per turn, when this card is targeted for an attack: You can target 1 Effect Monster in your Graveyard; until your next End Phase, this card's name becomes that target's, and replace this effect with that target's original effects. Like Timaeus and Critias, the banishing effect includes field spells and Pendulum monsters in the Pendulum Zones. The second effect gives the player access to effects like Exploder Dragon, Buster Blader, Wall of Illusion which, depending on the battle, can be very useful.

The Legendary Knights also fuse together to create th most difficult monster I have ever seen: Timaeus the Knight of Destiny.

"Legendary Knight Timaeus" + "Legendary Knight Hermos" + "Legendary Knight Critias"

Must be Special Summoned (from your Extra Deck) by sending the above cards you control to the Graveyard, and cannot be Special Summoned by other ways. (You do not use "Polymerization".) This card is unaffected by other card effects. If this card attacks or is attacked, during damage calculation (in either player's turn): You can activate this effect once per battle; this card's ATK and DEF become equal to the ATK of the monster on the field with the highest ATK (your choice, if tied). When this card is destroyed by battle: You can Special Summon 3 "Legendary Knight" monsters from your hand, Deck, and/or Graveyard, ignoring their Summoning conditions.

There is really only one way to defeat this card that I can think of and that’s to use Armory Arm. Timaeus’s effect can’t actually be used more than once. Once its ATK is set, it stays there regardless of if a stronger monster hits the field, so you would have to attack with your strongest monster and set the ATK at equal. On your next turn, Synchro summon Arm and equip it to your most powerful monster and attack again. Theoretically, it should destroy Timaeus but I haven’t seen it done so I’m not entirely sure, so I’m classing it as invincible for now until I see it defeated, but its first effect is actually misleading and may fixed if they re-errata it.