1.Effect monster with cool effect, but low atk/def (Mysterious Puppeteer, Lord of D., Time Wizard....)

2.Magnetic Ring

3.Attach Magnetic Ring to your effect monster

4.Magnetic Ring reduces atk/def of the effect monster by 500, but prevents the opponent from attacking it.

5.Result:Really weak effect monster that can't be attacked.

Pros

        effect monster still has its effect but can't be attacked

        the -500 atk doesn't matter because nobody uses effect monsters to attack

        the -500 def doesn't matter because it can't be attacked.

Cons

        opponent can use de-spell

        opponent can use change of heart to force it to attack a stronger monster, killing itself.