Zombie Master EFFECT ( question )

hi ..
this is a dialog between me and my friend about Zombie Master's effect check it then give ur help

my friend : i normal summoned Zombie Master then my opponent activate Bottomless Trap Hole .. can i activate his effect ?
me : no u can't it become removed from play .
my friend : ok .. but i still send 1 monster to grave .. it's priority .
me : no , i don't think so , because Bottomless is a chain to the summon of ur monster not to activation of his eff .. so ur monster become not here it removed .... i'll ask about that .

i finished
i said that to him because i thought the effect of Zombie Master is a cost effect (Ignition effect) not a trigger effect like Caius the Shadow Monarch's effect
if u have an explanition put it in ur reply , because there r alot of monsters has the same method of Zombie Master

at last .. thanks at all

Zombie Master has an ignition effect. That means when you summon him, you can retain your priority to activate his effect, securing it's place as Chain Link 1. A monster is discarded as a cost.
Bottomless is then activated as Chain Link 2, and the chain resolves backwards if no further cards are chained.

Bottomless destroys and removes Zombie Master.
Zombie Master's effect fizzles, because it has to be face-up when resolving the effect, so no zombie-type monster is special summoned from your graveyard, even though you already discarded a card.

thanks master .. i understand it

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