Lay an Egg

Lay an Egg
Group: Spell Card
Type: Spell
Set 1 Level-4 or lower Reptile-type monster in your Deck. It cannot be flipped face-up this turn, except by a card effect. You cannot Normal Summon this turn.

to

Lay an Egg
Group: Spell Card
Type: Spell
Special Summon 1 Reptile-Type monster face-down in Defense Position from your Deck. It cannot be flipped face-up this turn, except by a card effect. You cannot Normal Summon this turn.

Question: how can you flip something set face-up by a card effect if you "setting" something in your Deck? it will just go in your hand by then lol.

She actually meant by a morphing Jar #2's special summoning effect. lol
can

Special Summon 1 Reptile-Type monster face-down in Defense Position from your Deck. It cannot be Flip Summoned this turn, except by a card effect. You cannot Normal Summon this turn.

Just in case, random situation, we use this on the opponent's turn (via Catalyst Apprentice), they attack the face-down, and we don't know what to do.

Well if it by battle that spell's effect doesn't applies as the steps ignore most things except the said effect. But if not, then it self-destructed a punishment by the mechanicals of the Damage Step that it broke the rule and the attacking get a free pass through for direct attack or choosy another target if there another monster instead.