Edison format ruling
Thousand Energy
Card effect (current official text)Increase the original ATK and DEF of all face-up Level 2 Normal Monsters (except Tokens) on your side of the field by 1000 points until the End Phase. Destroy all Level 2 Normal Monsters on your side of the field during the End Phase.
Rulings
- If you Summon a monster after the resolution of Thousand Energy, it does not gain the +1000 ATK, but it is still destroyed during the End Phase because that effect is applied to all Level 2 Normal Monsters at that time.
- A monster affected by Thousand Energy is not destroyed if it is face-down during the End Phase.
- If a monster affected by Thousand Energy switches control to your opponent, it is not destroyed during the End Phase.
- If a monster affected by Thousand Energy has its Level changed so that it is not Level 2 during the End Phase, it is not destroyed.
- If you use Cost Down to make a Level 4 monster into a Level 2 monster, Summon it, and use Thousand Energy, during the End Phase you can choose which effect happens first, so you can restore it to Level 4 first by ending Cost Down's effect, and then it will not be destroyed by the effect of Thousand Energy.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Edison forum — sourced change requests get reviewed.