Slyfer has +1000 atk and def for each card in your had
Rainbow Dragon is ATK: 4000, DEF: 0.
Red Dragon Archfiend is ATK: 3000, DEF: 2000
The Winged Dragon Of Ra is the most unexpected surprise attack for players. Although the question is what's the ATK and DEF, it is unknown. When you get the card, the ATK and DEF is unknown.
2400 atk 2000 def
Stardust Dragon has ATK: 2500, DEF: 2000
no just its atk and def
The highest original (printed) ATK of any YuGiOh! Card is 5000 ATK. This can be found on 5 different cards - 3 Dragon-type monsters and 2 Machine-type monsters: 1) Dragon Master Knight (Dragon/Fusion/Effect - 5000 ATK/DEF) 2) Malefic Truth Dragon (Dragon/Effect - 5000 ATK/DEF) 3) Five-Headed Dragon (Dragon/Fusion/Effect - 5000 ATK/DEF) 4) Rocket Arrow Express (Machine/Effect - 5000 ATK/0 DEF) 5) Superdimensional Robot Galaxy Destroyer (Machine/Xyz/Effect - 5000 ATK/2000 DEF) Notably there has never been a 5000 ATK Synchro Monster, and also notable is that the Dragon-type 5000 ATK monsters have greater DEF than the Machine-types.
Not necessarily, as there are a few genuine monsters with 5000 ATK and DEF, namely Dragon Master Knight, Malefic Truth Dragon and Five-Headed Dragon.
The monster card with the "best"/highest ATK would be Dragon Master Knight, Five-Headed Dragon/ F.G.D., and Malefic Truth Dragon. All three monsters have 5000 ATK.
Exodia the Forbidden One has an ATK of 1000, and a DEF of 1000.
In terms of stats, Dragon Master Knight and Five-Headed Dragon each have 5000 ATK and DEF.
It has an 'undetermined' ATK and DEF, meaning it can't be searched for by cards that look for a specific ATK or DEF.Under some circumstances, it is considered to have '0' ATK and DEF. Such a sitation would be if it was attacked while Skill Drain is negating its ATK and DEF setting ability. For the purposes of Damage Calculation, it is considered to have 0 ATK and DEF.