yugioh speed duel duelists of shadows card list GX: Release Events – Yu-Gi-Oh! My Speed Duel decks! :

If an effect adds additional combat phases to a turn and a creature with a boast ability attacks more than once during that turn, its boast ability can still be activated only once

Which basically means, if youve got Questing Beast and an untapped Maze of Ith, odds are pretty good your opponents biggest and baddest creatures will look elsewhere during their attack steps

On resolution of that ability you put them on the stack without casting, so Trinishpere doesnt care about them

That happens to be exactly what this four mana Black Enchantment Artifact does, and we love it

also it remains on the field until the end phase of your next turn

Incapsula incident ID: 303000730023518026-14428195326464579