Building around such a versatile engine often requires a robust mana base and utility pieces to ensure you can activate his abilities repeatedly
What makes this card so lethal, though, is the fact that on every turn but yours, you can loan it out, ala Assault Suit, to wreak havoc on the rest of the table
your opponent can Special Summon 1 monster from their GY
The specific rule for commander damage doesn't specify that an opponent's commander had to deal the damage, just that a specific commander needs to deal damage
In this case youll get the threat and turn it face down as a 2/2
As a commander, Kefka can be ruthless, forcing your opponents to discard cards and sacrifice their permanents (whack a Tergrid in here to be extra mean)