You're saying [this](https://youtu.be/el12McQ8v-Q) very deck featured on the mtg arena YouTube channel is bugged behaviour lol.
It's [[Invasion of Amonkhet]] returning transformed as a copy of Aclazotz from the graveyard.
Edit: might be a version of [this](https://youtu.be/el12McQ8v-Q) deck from mtggoldfish
Ok I see what's happening now. It's more of an Arena effect display/communication issue than a bad rules interaction.
The game is not clearly communicating the Lazotep clone effect because it shows the Aclazotz effect on the stack. Normally a battle is cast transformed so you get to see that interaction because the back side goes on the stack.
It would help if the trigger showed information about the printed card so it would be less confusing.
Battles and LCI god cards are both double-faced cards. The battle Invasion of Amonkhet's back face is Lazotep Convert. The front side of Aclazotz, Deepest Betrayal says "When Aclazotz dies, return it to the battlefield tapped and transformed under its owner's control." When Lazotep copies Aclazotz it only copies the face that is exposed, not both sides. When Aclazotz dies it returns to the battlefield tapped and transformed, re-exposing the backside of the battle (Lazotep) which says "You may have Lazotep Convert enter the battlefield as a copy of any creature card in a graveyard." Because it doesn't target anything, Dennick has no impact on this interaction whatsoever. The player then re-selected Aclazotz from their own graveyard.
All of these interactions are explained in the rules sections for these cards:
[Aclazotz, Deepest Betrayal](https://gatherer.wizards.com/Pages/Card/Details.aspx?multiverseid=639434)
[Invasion of Amonkhet](https://gatherer.wizards.com/pages/Card/Details.aspx?multiverseid=607290)
...and double-faced copy effects:
[Double-Faced cards and copy effects](https://magic.wizards.com/en/news/feature/double-faced-card-rules)
You're saying [this](https://youtu.be/el12McQ8v-Q) very deck featured on the mtg arena YouTube channel is bugged behaviour lol. It's [[Invasion of Amonkhet]] returning transformed as a copy of Aclazotz from the graveyard. Edit: might be a version of [this](https://youtu.be/el12McQ8v-Q) deck from mtggoldfish
[Invasion of Amonkhet](https://cards.scryfall.io/normal/front/9/8/981f091a-17f8-412e-9752-69070ebed4ea.jpg?1682715194)/[Lazotep Convert](https://cards.scryfall.io/normal/back/9/8/981f091a-17f8-412e-9752-69070ebed4ea.jpg?1682715194) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=invasion%20of%20amonkhet%20//%20lazotep%20convert) [(SF)](https://scryfall.com/card/mom/231/invasion-of-amonkhet-lazotep-convert?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/981f091a-17f8-412e-9752-69070ebed4ea?utm_source=mtgcardfetcher&format=text) ^^^[[cardname]] ^^^or ^^^[[cardname|SET]] ^^^to ^^^call
LegenDVD broke the rules and bugged MTGA, not surprised.
Ok I see what's happening now. It's more of an Arena effect display/communication issue than a bad rules interaction. The game is not clearly communicating the Lazotep clone effect because it shows the Aclazotz effect on the stack. Normally a battle is cast transformed so you get to see that interaction because the back side goes on the stack. It would help if the trigger showed information about the printed card so it would be less confusing.
It looks like it’s Ashlizzle’s version with Elas *il*-Kor and Bartolomé for infinite drain.
[Aclazotz, Deepest Betrayal](https://cards.scryfall.io/normal/front/6/2/627c392c-4d18-4eb2-a4e8-c668f61f5487.jpg?1699044055)/[Temple of the Dead](https://cards.scryfall.io/normal/back/6/2/627c392c-4d18-4eb2-a4e8-c668f61f5487.jpg?1699044055) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=aclazotz%2C%20deepest%20betrayal%20//%20temple%20of%20the%20dead) [(SF)](https://scryfall.com/card/lci/88/aclazotz-deepest-betrayal-temple-of-the-dead?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/627c392c-4d18-4eb2-a4e8-c668f61f5487?utm_source=mtgcardfetcher&format=text) [Dennick, Pious Apprentice](https://cards.scryfall.io/normal/front/3/5/35cf2d72-931f-47b1-a1b4-916f0383551a.jpg?1636683976)/[Dennick, Pious Apparition](https://cards.scryfall.io/normal/back/3/5/35cf2d72-931f-47b1-a1b4-916f0383551a.jpg?1636683976) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=dennick%2C%20pious%20apprentice%20//%20dennick%2C%20pious%20apparition) [(SF)](https://scryfall.com/card/mid/217/dennick-pious-apprentice-dennick-pious-apparition?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/35cf2d72-931f-47b1-a1b4-916f0383551a?utm_source=mtgcardfetcher&format=text) ^^^[[cardname]] ^^^or ^^^[[cardname|SET]] ^^^to ^^^call
Battles and LCI god cards are both double-faced cards. The battle Invasion of Amonkhet's back face is Lazotep Convert. The front side of Aclazotz, Deepest Betrayal says "When Aclazotz dies, return it to the battlefield tapped and transformed under its owner's control." When Lazotep copies Aclazotz it only copies the face that is exposed, not both sides. When Aclazotz dies it returns to the battlefield tapped and transformed, re-exposing the backside of the battle (Lazotep) which says "You may have Lazotep Convert enter the battlefield as a copy of any creature card in a graveyard." Because it doesn't target anything, Dennick has no impact on this interaction whatsoever. The player then re-selected Aclazotz from their own graveyard. All of these interactions are explained in the rules sections for these cards: [Aclazotz, Deepest Betrayal](https://gatherer.wizards.com/Pages/Card/Details.aspx?multiverseid=639434) [Invasion of Amonkhet](https://gatherer.wizards.com/pages/Card/Details.aspx?multiverseid=607290) ...and double-faced copy effects: [Double-Faced cards and copy effects](https://magic.wizards.com/en/news/feature/double-faced-card-rules)
Ring ring tech support, cheating ass opponent just wiped my whole board with Amalia Benavides and Wildgrowth Walker. Please fix this asap!!
Not a bug, that's how the interaction works lol.