Problem is that even if youre at 40+ life, the moment you cast Felidar Sovereign, other players will try their best to attack you or kill your win condition, making this a little more balanced
Wall of Ice and Wall of Wood
This was partly because there wasn't a need for them and partly because we were being a little shy due to their over-performance in tournament formats
3 Ixhel, Scion Of Atraxa A Latticework Of Toxicity One of the more complicated commanders dedicated to poisoning out your opponents, Ixhel, Scion of Atraxa comes loaded with keywords and abilities to poison your opponents out of the game
She also has an activated ability that turns lands into creatures, which is a reasonable backup plan if the game goes long
Since it puts +1/+1 counters on creatures entering play from the graveyard, it sets up an easy infinite combo with any persist creature and a free sacrifice outlet