Nuclear Core

Nuclear Core
Group: Spell Card
Type: Spell
Icon:Equip
The equipped monster's Level is increased by 1 each turn.

Nuclear Core
Group: Spell Card
Type: Spell
Icon:Equip
The equipped monster's Level is increased by 1 each turn. As long as the equipped monster is Level 6 or higher, it cannot be destroyed by card effects. As long as the equipped monster is Level 9, it cannot be banished. If the equipped monster is Level 13 or higher, you can send this card to the Graveyard: destroy all other monsters on the field.

also fine

I forget, which Phase does the Level increase? Beginning of Draw Phase?

I forget Let's errata it too then.

The equipped monster's Level is increased by 1 during each Standby Phase. As long as the equipped monster is Level 6 or higher, it cannot be destroyed by card effects. As long as the equipped monster is Level 9, it cannot be banished. If the equipped monster is Level 13 or higher, you can send this card to the Graveyard: destroy all other monsters on the field.