The sweet spot is probably around 5 mana so that you can have two creatures that give your tokens +1/+1 counters, but you can really sink as much mana as you want into that squad ability
Cards like Seal of Doom, Seal of Primordium, Spore Frog, and Omen of the Sea are cheap ways to get spell-like effects from permanents, and many Sultai decks benefit from these kind of cards
Based on my (admittedly raw) data that I did spend a day with prior to editing my piece and massaging my numbers, you can see that I use the first three targets around 80% of the time
A card like this doesnt have the same downside with the mechanics retirement, but normal mana timing restrictions still happen
Elemental Bond + Tribute to the World Tree Elemental Bond versus Garruk's Uprising sparks an interesting discussion, but I favor Elemental Bond as it has a lower threshold for that juicy card draw
Gary in Magic slang, which is a staple in mono-black Commander decks