To give perspective, one of the stronger attacker in the game at the time, Hitmonchan, was able to deal 20 or 40 damage max at a cost of three Energy, thus taking several turns to KO Chansey and Charizard
Note that if you attack a monster and your opponent controls no more monsters, you cannot attack directly, due to the effect allowing it to make attacks on monsters up to the number of materials +1
Sidar Jabari must be on the battlefield or in the command zone at the moment you attack with one or more Knights and also as the triggered ability tries to resolve
Zodiac Dragon was one of the 12 Zodiac creature cycle, all of which are worth nought except for Zodiac Dragon
If that werent enough, Joey could also fuse his favorite warrior with Yugis iconic Dark Magician to create the devastating Dark Flare Knight which can also bring out the mystical Mirage Knight