Is the Yu-Gi-Oh card Sorcerer of Dark Magic not a good card?

It depends on if you have enough support for him. Here's his effect if anyone else is curious: This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by offering 2 Level 6 or higher Spellcaster-Type monsters on your side of the field as Tributes. As long as this card remains face-up on the field, you can negate the activation of Trap Cards, and destroy them.

He's like Jinzo, except Trap cards can actually be activated, but you'll most likely negate & destroy them with his effect. But he only negates Traps that are activated, so Continuous Traps and other Trap cards already active on the field will not be negated-only newly activated ones while he's face-up. But the controller is still free to activate Traps unlike Jinzo.

Here's some tips to contruct a deck on using Sorcerer of Dark Magic (SoDM):

• Use Magician's Circle and/or Magical Dimension to bring out Level 6 Spellcasters like Dark Magician Girl
• Sage's Stone and Dark Magician Girl gives Dark Magician- a second monster to tribute
• Use Magicial Scientist to Special Summon two Sanwitches to tribute
• Use Mystic Tomato to get Allure Queen LV7. It maybe useless on its own, but it meets the requirements to summon SoDM
• Center the deck on negation by including cards to negate Spells like Imperial Order, Horus the Black Flame Dragon, Spell Canceller, etc.

With the right support, SoDM is a valuable card with a great effect and some nice ATK and DEF stats, too!

It works best if it is on the field at the same time with a Dark Paladin.