Shadow Knight 2700 ATK, DARK / Warrior Effect: Can attack twice per turn if your opponent controls a LIGHT monster
Warrior Lady+ 1Heavy Storm+ 3Reload+ 1Sangan+ 1Marshmallon+ 2Mystical Shine Ball+ 2Solemn Judgment+ 3Double Coston+ 3Archfiend Soldier+ 1Torrential Tribute+ 1Pot of Greed+ 3The Wicked Dreadroot+ 2The Agent of Creation - Venus+ 1Pot of Avarice+ 1Lightning Vortex+ 1Premature Burial+ 1Nobleman of Crossout+ 1Ultimate Offering+ 3Goblin Elite Attack Force+ 1Compulsory Evacuation Device+ 3Giant Germ+ 1Call of the Haunted Deck Breakdown Archetype and card type distribution for this list
The train that comes out like this is strong Over 3,000 RBIs and 4,000 lines of defensive power
Temporary indestructibility (once per turn, this card can't be destroyed by card effects, etc) would make for a better medium between complete indestructibility or none at all
Its continuous effect can also deal with monsters used as Droplet costs, so just placing it next to Apollousa, True Shien, or True Shien makes for a compromise board that limits the opponent's board-breaking cards