1) Dark Dive Bomber
2) True Six Samurai- Shi En
3) Trishula Dragon of the Ice Barrier
4) Brionac Dragon of Ice Barrier
5) Black Rose Dragon
6) Star dust Dragon
7) Tech Genus Hyper Librarian
8) Formula Synchron
9) Scrap Dragon
10) Goyou Guardian
Time for some explanation. You really cant deny that DDB takes the top spot. It dominated a whole format of Yugioh whereby the first Cat player to draw a god hand and drops DDB will win.
I still remember being one of the few OCG players on TCGplayer.com, and explaining to them how good DDB was, and i was mocked by most who thought that nobody would even touch DDB.
True SS Shi En is the second most powerful card because of how easy he is able to be summoned and the synergy he has with his deck. It can also negate a free spell/ trap which makes this card so good, and your opponent has to waste a Dark Hole/ Book of Moon just to force this card's negation effect. Then if he wants to make more moves, he still hasn't cleared the possiblity of multiple books/ warnings/ magatamas face down on the six samurai player's field.
When i was in KL i played against Sean (a Six sam player with god luck) who would open with gateway and good cards each game. Traumatic experience. (no he didn't stack, he just shuffles well)
Above all, Six Sam Shi En is incredibly difficult to destroy, since you can just substitute a random kizan or whatever samurai on the field to prevent Shi En to be destroyed. Truly the most powerful and annoying synchro in the game right now.
Trishula is self explanatory because usually, whoever summons it first will win the game. Brionac is the best OTK machine around and is incredibly easy to summon (6 is a magic number for many decks around)
Black Rose came fifth because it can perform Wrath of God. Stardust is still a good control option so why not.
Tech genus Hyper Librarian is there because of draw turbo decks like Fish and Fabled draw engines. Formula Synchron is a pot of greed in disguise too, combined with the librarian. i'd like to see formula synchron gettin hit in the upcoming banlist.
Then Scrap Dragon and Goyou, which are 2 decent generic staples in everybody's extra deck.
Take note that this list isn't affected by favoritism. I hate TSS Shi En. Nuff said.
My Favorite list will probably go something like this:
3) black rose
4) scrap dragon
5) naturia beast
7) collosal fighter
8) junk destroyer
9) fabled raging