Another upkeep question

[Dmon3k]

I was playing someone today and ran into a question, I took their word for it during the game, but for my own knowledge wanted to see what the ruling would be in this situation.

I was playing a forcemaster and had several of my oppnent's creatures either charmed or in force holds. There was a Mordor's Obelisk on the field giving all non mage creatures upkeep plus 1.

At the start of the the round I paid my upkeeps to keep my charms/force holds on, my opponent then decided to not pay the upkeep so all his creatures were destroyed.

I thought it was a pretty slick move because I wasted the mana and couldn't get it back, but now I'm left wondering because I can't pay upkeep if there is no creature so should I have waited to see if he paid upkeep on the creature first, should it have been determined by who has initiative since it is a timing issue, or was he right and I'm just stuck dealing with that strategy going forward?

Any clarification would be helpful.

[lettucemode]

Both upkeep effects happen at the same time, so whoever had initiative would decide. If you had initiative, you could have told him that he must pay/not pay upkeep on his creatures first. If he had initiative then he could/would do what he did.

[barriecritzer]

Good to know, I honestly don't remember which one of us had initiative.

[Shad0w]

Both upkeep effects happen at the same time, so whoever had initiative would decide. If you had initiative, you could have told him that he must pay/not pay upkeep on his creatures first. If he had initiative then he could/would do what he did.

Lettuce is correct. Both cards affect the same object at the same time so it wouldfall to initiative