During your Standby Phase, you can Special Summon a Level 6 or Level 8 monster from either player's Graveyard in face-up Defense Position. That monster is destroyed during the End Phase.
That's the first part of the effect. I'm not sure what you want the last part to do, so I can't really help there. The card itself is interesting, and it is balanced enough. I would add a clause about the monster not being allowed to change the battle position, but it's not needed.
Eh, I guess I'll throw my favorite card I've made in here.
As long as this card is on the Field, neither player may draw cards during their Draw Phase. Each player draws 1 card from their Deck during their End Phase. Neither player may Normal Summon or Set during their turn. Once during your opponent's turn, you may Normal Summon or Set 1 monster from your Hand. If a monster is destroyed and you would take damage, you instead gain the same amount. Once while this card is face-up on the Field, if a player's Life Points is 10000 or more, both players must discard their hand and draw 3 cards. Any card sent to the Graveyard is sent to the bottom of the deck instead. If a player has no cards in their hand during their Standby Phase, they must draw 1 card. When a monster is summoned in Attack Position, flip it face-down without changing the battle position. A monster in face-down Attack Position cannot declare an attack.