[@dragonmancer]

Few things:
First, cards whose names are always treated as the same name as another card, regardless of what they are, will limit the number of cards with that name to 3. Examples are Polymerization and [url=http://yugioh.wikia.com/wiki/Fusion_Substitute]Fusion Substitute[/url] as well as Umi and A Legendary Ocean. So, you can't have more than a total of 3 Tyrant Dragon and Tyrant Dragon Overlord cards. I'm not actually sure about Supreme Dragon Tyrant on this regard since it's not in the Main Deck, but I would assume the same restriction applies. Perhaps have "This card's name becomes 'Tyrant Dragon' while it is on the field or in the Graveyard" instead if you really want to keep it the way you want it.

Second, Tail Spear of the Tyrant Dragon is a little awkward. You don't need to have the initial clause "This card is always treated as a Tyrant Dragon spell card" if the words "Tyrant Dragon" are already in its name. You also have "If you control no monsters" as a requirement, yet you allow "tributing dragon-type monsters from both your side of the field" in it. A useless effect there. You also don't need "you may [b]unequip[/b] and destroy this card instead", just put "you can destroy this card instead" since it'll be unequipped automatically when it's destroyed, y'know? Heck, I'm not even sure that effect should be there at all, considering you already have 1000 ATK and piercing.

Third: Tyrant Dragon Overlord. You get to summon this card using monsters from your graveyard, and by doing so search out a card from your deck. Furthermore, it's immune to all traps. It's just a straight upgrade from the original Tyrant Dragon, and that's not exactly something you should want, nor would it even make sense to reduce the original Tyrant Dragon to being fusion material fodder. It should definitely be nerfed, or even altered to have a different effect from the original Tyrant Dragon and therefore giving both a good reason to be around.

Fourth: Supreme Dragon Tyrant. The "Dragon's Mirror" effect is rather unnecessary, so that should be removed, imo. The 3900 ATK seems too high to include a "gain 400 ATK" as well, and you already have Trap and Monster effect immunity on it. Why does it even have Monster effect immunity, anyway? Trap immunity is enough. At the very least, you should choose the 400 ATK increase or Trap immunity. It wouldn't be fair to have both.