OCG Rulings: (Credits to Konami and Yugioh wiki)

Quote :

Paying 1000 Life Points is a cost.[1]
This card cannot be activated during the Damage Step.[1]
The effect of "Soul Drain" prevents the effects of monsters that are in the Graveyard or that are banished from being activated, so even if "Soul Drain" is active, effects that are activated on the field like "Cardcar D" or "Rescue Rabbit" can be activated.[2]
If "Soul Drain" is applying its effect that prevents monsters in the Graveyard or that are banished from activating their effects, a "Giant Rat" or "Mystic Tomato" that have been destroyed in battle and sent to the Graveyard cannot activate their effects.[3]
Special Summoning "Grapha, Dragon Lord of Dark World" doesn't start a chain. Therefore, even if "Soul Drain" is active, "Grapha, Dragon Lord of Dark World" can be Special Summoned by returning a "Dark World" monster to the hand.[4]
The effect of "Honest" activates in the hand and sends "Honest" to the Graveyard as a cost. Therefore, even if the effect of "Soul Drain" is being applied, the effect of "Honest" can be activated.[5]

Cards which are hurt from soul drain:

*Stardust cannot be special summoned from the graveyard by it's effect
*Card effects which activate when they are destroyed (such as elemental hero absolute zero or giant rat)
*Monster effects which special summon themselves from the graveyard cannot be used such as elemental dragons or Ronintonin and Treeborn Frog

Ruling tip:

if you chain it to an effect that has already activated, that effect won't be negated. Soul Drain doesn't negate the effects of cards in the grave or that are banished, it merely prevents them from activating effects that start a chain; therefore, cards that don't start a chain such as Machina Fortress can still use their effects.

Soul drain against decks

Soul drain manages to hurt many decks here is some of the list:Elemental dragons, Mermail atlanteans, Darkworld, Infernity,

So what are your views on soul drain? Comment below.