After using this card's third effect, you can attack with this card, and then target it with "Forbidden Chalice" to give it 400 ATK and still allow you to attack with other monsters, but keep in mind that this card will no longer be protected from being destroyed.
Alternatively, if you have "Odd-Eyes Persona Dragon" on the field with this card, you can use Persona's effect to negate this card's effects until the end of the turn (This effect can be used in the battle phase as well).
Depending on the monster targeted by this card's effect, you will also recover the LP drained when "Soul Charge" resolved.
Since this card halves battle damage to your opponent, you can use cards like "Junk Barrage" or "Mini-Guts" to inflict effect damage.
Remember however, that this card's effect does not need to be activated during Main Phase 1, as such if your opponent has 2 monsters on the field you can first attack the weaker one for full damage, then on your Main Phase 2 you can use this card's effect on the stronger monster.
You can easily Summon this card by Summoning "Armageddon Knight" through the effect of "Summoner Monk". When Armageddon Knight is Summoned, you can use his effect to send "Plaguespreader Zombie" to the Graveyard, and Special Summon it by returning a card from your hand to the Deck.