Does Fist of Suns allow you to play your commander for its alternative cost?
Asked by Kingpin4682 8 years ago
Can you play your commander using only 1 of each colour while Fist of Suns is on the field under your control?
Raging_Squiggle says... #2
To elaborate on Gidgetimer's post:
The formula for casting goes like this:
(Casting cost or Alternative cost) + Additional Costs - Cost Reductions
601.2e ...The total cost is the mana cost or alternative cost (as determined in rule 601.2b), plus all additional costs and cost increases, and minus all cost reductions...
As he said, the act of paying an extra 
per time your commander has been cast from the command zone is an additional cost.
So, you could use this for your formula if you want:
+ (times the number of times your commander has been cast already) - Any Cost Reductions.
November 20, 2015 1:02 a.m.
Kingpin4682 says... #3
Thanks to both of you. This really helps me a lot.
Gidgetimer says... Accepted answer #1
Yes you can play your commander for
when Fist of Suns is out. It doesn't function how you want it to though. Fist of Suns creates an alternate casting cost, so you can pay it instead of the cost printed in the upper right hand corner of your commander. The commander tax is an additional cost that gets added when determining the total casting cost. So you would pay 
if your commander had not yet been cast, 
if it was the second time, and so on.
November 20, 2015 12:45 a.m.