Theres some real competition, but the eminence ability puts Markov over the top, generating literal free tokens, then coming down to put a swift end to the game
Dark Synchro Monsters are still treated as Synchro Monsters, and effects that apply to Synchro Monsters, such as "Synchro Destructor", also apply to Dark Synchro Monsters
Eating a 1/1 or 2/2 and taking some damage from other small creatures is bearable, but against Steel Leaf Champion they are taking enough damage that they likely must trade, letting your smaller creatures get through more easily
While it could only at most garner two-for-one card advantage, this often was enough to fuel three-color, base-white decks such as the oddly named "PT Junk" and "PT Jank" decks
What are the rules for Party in Magic: The Gathering
If you lose control of Kellogg before its last ability resolves, you won't gain control of the target creature at all