The iconography of the King Protector has always been a fascinating one but as we investigate further into it, we begin to see greater details of the character and function of this emanation of Manjushri.
The flaming sword of Manjushri of course symbolizes the Wisdom that is required to cut through the Ignorance of man that keeps them in samsara. The difference between Manjushri's sword and the sword that Dorje Shugden (as wrathful Manjushri) wields is that the Protector's sword is depicted as having a wavy blade. This is interesting because the wave bladed sword actually reflects the character of the Indonesian spirit-sword (keris) which is known to demand the enemy's blood once drawn and furthermore, the wavy design also resembles the the Tibetan 'water-knife' used to gut fish.
Combined the wavy sword of Dorje Shugden that is drawn and held aloft, reflects the Protector's strong and intense plan to draw blood of the enemy of man's liberation which is Ignorance. In Tibetan Buddhism the 'water-knife' is also used to symbolize the severing of cyclic existence or samsara as the wavy water knife cuts away the guts (emptiness of inherent existence), scales (phenomenal appearances), heads (cycle of birth and rebirth) and tails (karmic propensities) of all sentient beings. So more than just providing Wisdom, Dorje Shugden aggressively seeks to liberate the practitioner from the trap of samsara.
In addition, older thangkas of Dorje Shugden shows the Protector to be holding the enemy's heart close to his open mouth as if to eat the heart. In Tibetan Buddhist iconography, the tearing and eating of an enemy's heart with a curvy knife symbolizes the severance of the root of the 5 kleshas which are Ignorance, Attachment, Aversion, Pride and Jealousy and their transformation (through eating) into the five Buddha Wisdoms. (Page 165, Handbook Of Tibetan Buddhist Symbols-R.Beer)
In my opinion, these additional two iconographic details hint at Dorje Shugden's tremendous ability in getting the practitioner out of samsara, beyond being a powerful and highly compassionate and efficacious Dharma Protector.