Nope. Dethrone specifies that it occurs when it ATTACKS, which any creatures that enter the battlefield already attacking didn't do. It never went from a state of not attacking, to a state of attacking - it was always attacking. Put another way, it was never declared as an attacker.
Hopefully that makes sense. Anyway, it's a definite no.
Hopefully that makes sense. Anyway, it's a definite no.
Btw this is the wrong subforum for rules questions. The correct subforum is here: https://www.mtgsalvation.com/forums/magic-fundamentals/magic-rulings
EDH Primers
Phelddagrif - Zirilan
EDH
Thrasios+Bruse - Pang - Sasaya - Wydwen - Feather - Rona - Toshiro - Sylvia+Khorvath - Geth - QMarchesa - Firesong - Athreos - Arixmethes - Isperia - Etali - Silas+Sidar - Saskia - Virtus+Gorm - Kynaios - Naban - Aryel - Mizzix - Kazuul - Tymna+Kraum - Sidar+Tymna - Ayli - Gwendlyn - Phelddagrif 4 - Liliana - Kaervek - Phelddagrif 3 - Mairsil - Scarab - Child - Phenax - Shirei - Thada - Depala - Circu - Kytheon - GrenzoHR - Phelddagrif - Reyhan+Kraum - Toshiro - Varolz - Nin - Ojutai - Tasigur - Zedruu - Uril - Edric - Wort - Zurgo - Nahiri - Grenzo - Kozilek - Yisan - Ink-Treader - Yisan - Brago - Sidisi - Toshiro - Alexi - Sygg - Brimaz - Sek'Kuar - Marchesa - Vish Kal - Iroas - Phelddagrif - Ephara - Derevi - Glissa - Wanderer - Saffi - Melek - Xiahou Dun - Lazav - Lin Sivvi - Zirilan - Glissa
PDH - Drake - Graverobber - Izzet GM - Tallowisp - Symbiote Brawl - Feather - Ugin - Jace - Scarab - Angrath - Vraska - Kumena Oathbreaker - Wrenn&6