Yugioh Red Eyes Darkness Metal Dragon...?

What's up with everyone lately mentioning him for the best dragon card deck suggestion?

Specially cause i read the deck list they mention

the last example i saw:

3 Red Eyes Darkness Metal Dragon

2 Van'Dalgyon the Dark Dragon Lord

1 Dark Horus

1 tyrant Dragon

2 Prime Material Dragon

1 cyber Dragon

1 spirit Reaper

3 Axe Dragonute

3 Blizzard Dragon

2 exploder Dragon

1 Twin Headed Behemoth

2 masked Dragon

1 Brain Control

1 Mystical Space

1 Heavy Storm

1 Monster Reborn

1 Mausoleum of the Emperor

1 Lightning Vortex

1 Smashing Ground

2 Stamping Destructions

3 Hand Destructions

1 Dragon's Mirror

3 Solemn Judgement

3 Magic Drain

2 Divine Wrath

1 Mirror Force

1 Torrential Tribute

and i wonder... why play that card in there if you lack the cards that let you summon him... You must play red eyes black dragon, sacrifice him for r.e. darkness dragon equip him for that crazy trap, and finally sacrifice this one as well for Red Eyes Darkness Metal Dragon...

Till all this is made i have gathered exodia 10 times.

Not to mention it's a card i only saw in the anime and wikia till now.

Or perhaps is it we are talking for a different card and i don't know it yet? (Since i was preparing for the exams lately i didn't have time to deal with the game).

Finally recall i have never asked a question without voting a best answer, so reply with no fear.