Mobbed by mini ball Lightnings

[Deathseide]

{eternal witness} x2, {aluren} {phyrexian Altar}, {lightning coils}

That should cover the mana costs
To make it even more potent add in a {doubling season} which not only doubles the counters on the coils but also the creatures being produced.

[scarsabrex]

not seeing how you're paying for the witnesses medallion reduces it to GG, and altar can produce G but you still have a G per cycle to go before this infinite.

[Deathseide]

Had modified the combo to match workability