I'm not sure whether or not the word "beginning" actually matters here.
In other words, I want to know if The Scarab God is going to count the zombies from stairwell in its ability or if "beginning" means that The Scarab Gods ability will resolve before the tokens are created.
Both cards trigger at the same time. And as the controller of all those triggers, you choose their relative order on the stack. When The Scarab God's trigger resolves, it counts the number of zombies you control, so it is beneficial for you to put the Stairwell's token creating trigger on top, so that those tokens get counted. Note, that the cumulative upkeep trigger should be below the token trigger if you don't intend to pay.
"At the beginning of the/your/the next/etc. upkeep" is just the time the triggers go off.
Tombstone Stairwell
I'm not sure whether or not the word "beginning" actually matters here.
In other words, I want to know if The Scarab God is going to count the zombies from stairwell in its ability or if "beginning" means that The Scarab Gods ability will resolve before the tokens are created.
"At the beginning of the/your/the next/etc. upkeep" is just the time the triggers go off.
Former Rules Advisor
"Everything's better with pirates." - Lodge
(The Gamers: Dorkness Rising)
"Any sufficiently analyzed magic is indistinguishable from science."
(Girl Genius - Fairy Tale Theater Break - Cinderella, end of volume 8)