Similar to Draco Face-Off, Interrupted Kaiju Slumber does great things for no cost. As a Normal Spell Card, Interrupted Kaiju Slumber starts its effect with destroying as many monsters on the field as possible. Then you get to go through the deck to Special Summon on each side of the field two Kaiju monsters to battle in attack position as long as they have different names. Since it's your choice of monsters, even a non-Kaiju deck could splash 3 of 2 different Kaijus and 3 of this for very consistent and easy disruption. You wouldn't even need the Field Spell. 

Anyway, this card isn't done yet. Any turn but the one it was sent to the Graveyard, Interrupted Kaiju Slumber can banish itself to let you search a Kaiju from the Deck to your hand. So you can set this as a bluff and let your opponent destroy it for you to get a free search on your next turn. At least you can only activate this once per turn, but I still think this is a little over powered. 
 
Score: 4/5 Dark Hole plus Special Summon plus Free Search = Great!
Art: 4/5 

First off, I love how the card art features the Godzilla and Gamera-based monsters. Nice touch, Konami.
 
Now let's get to the card proper: since the Kaiju cards are hard to draw out, this card helps speed things up immensely. It also destroys most Monsters currently on the board, except for the ones who can only be hit by target effects. The best part though, is that this card lets you perform the main purpose of Kaiju monsters: to give your opponent the weaker Kaiju and kill it with a bigger one.

This card gives you one more speed boost the turn after it's activated; removing it from play lets you grab another Kaiju from the deck. All of this is great for the theme, but I think the theme is still too young to be competitive. Just a couple more Kaiju and cards like these will do the trick. But for now, hold onto this and other Kaiju cards for the future.
 
Score: 5/5 (theme overall is only about 2/5, sadly)