Ancient City - Rainbow Ruins

I was playing someone, it was unrated so I didnt care too much and it was recorded so I didnt wanna ask a mod while it was going on, but when my opponent has 3 cbeasts in teh spell/trap zone, can he send them from the spell/trap zone to negate my spells? The wikia ruling says:

Yugioh Wikia wrote:For the "3+" effect, you have to send a "Crystal Beast" Monster to the Graveyard. You cannot send a "Crystal Beast" Spell Card. This is a cost.[6]

Has to be Monster Zone ones, not S/T ones because the S/T ones are Continuous Spells, NOT Monsters.