Possible New Mechanic: Fecund

So I tossed out one of my partnered animal cycle templates for feedback over at Goblin Artisans and a couple responses suggested it would have memory issues (true) and would create removal pressure (also true) too soon. Another suggested using a counter that would be removed to create a second creature, which is a problem for a set with a heavy focus on +1/+1 counters. So that's out.

But both responses got me thinking about other ways to gatekeep making creature tokens. The more I design, the more I realize token creatures are a vital, central part of the set that need a mechanic. I didn't want to use populate, but I really needed a way to show quick reproduction. I keep using the word "fecund" and realized, "Hey, that could be a mechanic."

So a way of triggering creature token reproduction has been bouncing around in my head all day (While I'm supposed to be working, no less.) I have two versions so far.

Version One:

So the way it works, is when this enters the battlefield, if you control another snake, you get an additional copy of this creature. The token copy does not have fecund because this is an enter-the-battlefield effect and would therefore immediately go infinite.

An alternate possibility representing wild, magical cross-breeding is this one:

In this version, when Thistle Adder enters the battlefield, if you have any other creature with the fecund ability, you get another snake. The idea being that the Thistle Adder breeds with the other creature.

I think this second version is more interesting, thematically more resonant with the set's concept, and keeps it from drifting too tribal. It would go great with green-blue concepts of quick evolution I'm trying to brainstorm. On the other hand, it's a bit creepy (we are talking about interspecies sex here) and keeps it from being used on humanoid creatures (because we are talking about interspecies sex). That's maybe okay. There will be other spells that can make humanoid tokens.

I see this in being in green (snakes and spiders), white (hounds and birds) and blue (birds and perhaps some sea creatures). I'm thinking of keeping it very, very limited in red and black. Maybe just a couple of red lizards and only black rats. Even though the vermin theme in G/B loves this mechanic, black already has access to a lot of mutate and reave. Black is getting maybe too many things in this set.