Tengu format ruling
Koa'ki Meiru Maximus

Card effect (current official text)This card cannot be Normal Summoned or Set. This card can only be Special Summoned by removing from play 1 "Iron Core of Koa'ki Meiru" from your hand. During each of your End Phases, destroy this card unless you send 1 "Iron Core of Koa'ki Meiru" or 1 "Koa'ki Meiru" monster from your hand to the Graveyard. Once per turn, during your Main Phase, you can select and destroy 1 card your opponent controls.
Rulings
- The Ⓜ in this card's text is a maintenance cost. It is not an effect, does not activate, and can't be negated.
- As long as this card was initially Special Summoned by its own procedure (and the summon wasn't negated), you can Summon it from the GY with card effects.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.