Kavu Primarch

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If Kavu Primarch was kicked, it enters with four +1/+1 counters on it.

Dominaria Remastered

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If Kavu Primarch was kicked, it enters the battlefield with four +1/+1 counters on it.

Time Spiral Remastered

The List

Modern Masters 2015

Future Sight

Convoke (Each creature you tap while playing this spell reduces its total cost by {1} or by one mana of that creature's color.)
Kicker {4} (You may pay an additional {4} as you play this spell.)
If the kicker cost was paid, Kavu Primarch comes into play with four +1/+1 counters on it.

Because convoke isn't an alternative cost, it can be used in conjunction with alternative costs.

If a creature you control has a mana ability with {T} in the cost, activating that ability while casting a spell with convoke will result in the creature being tapped before you pay the spell's costs. You won't be able to tap it again for convoke. Similarly, if you sacrifice a creature to activate a mana ability while casting a spell with convoke, that creature won't be on the battlefield when you pay the spell's costs, so you won't be able to tap it for convoke.

Tapping a multicolored creature using convoke will pay for {1} or one mana of your choice of any of that creature's colors.

Tapping an untapped creature that's attacking or blocking to convoke a spell won't cause that creature to stop attacking or blocking.

When calculating a spell's total cost, include any alternative costs, additional costs, or anything else that increases or reduces the cost to cast the spell. Convoke applies after the total cost is calculated. Convoke doesn't change a spell's mana cost or mana value.

You can tap any untapped creature you control to convoke a spell, even one you haven't controlled continuously since the beginning of your most recent turn.