You can activate Lose 1 Turn when you control no special summoned monsters, and if you do, monsters that are special summoned to the field cannot use their effects this turn (and special summoned effect monsters are changed to defense position)
Elsha is another great commander for a spell-heavy deck, and our friends at the Command Zone podcast have some recommendations for how to build around her
While all the "Forbidden" cards show that she's used items that she wasn't supposed to use, most of the cards with "Solemn" in the name show a man punishing her for this
That monsters effects are negated the turn it is summoned
For today's list I am going to look either at powerhouses that were overdue for a reprinting, or a strong utility card that has never seen another day in the sun
She appears in the Millennium World arc as an NPC during Dark Bakura's Shadow RPG game, and her Ka is the Dark Magician Girl