Goat format ruling
Mystic Swordsman LV2
Card effect (current official text)At the start of the Damage Step, if this card attacked a face-down Defense Position monster: Destroy that monster. During the End Phase, if this card destroyed a monster by battle this turn: You can send this face-up card to the Graveyard; Special Summon 1 "Mystic Swordsman LV4" from your hand or Deck.
Rulings
- If Mystic Swordsman LV2 attacks a face-down Defense Position monster, that monster is destroyed by Mystic Swordsman LV2’s effect, not as a result of battle. So you cannot use its second effect to Special Summon Mystic Swordsman LV4 during the End Phase.
- If a level monster fulfills its condition to Special Summon the next-highest level (for example, if Armed Dragon LV5 destroys a monster as a result of battle), and the level monster is then Set, or removed from play permanently, or sent to the GY and then Special Summoned from the GY, then its condition is reset and it is no longer considered to have met the condition to level up to the next level.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Goat forum — sourced change requests get reviewed.