I wasn't sure about reusing an existing planeswalker, but I really didn't want to bother inventing a new one, so I picked a reasonably helpful white- green- or blue- colored planeswalker already known to have visited Zendikar.

I think Allies is obviously a bit of a narrow theme for a real planeswalker, but I think for the challenge I can imagine a set where more allies are printed.

I also considered a plus ability putting a small ally into play, and a tutor ability, but I decided that what an Ally deck probably wanted was something that can help it keep playing an ally per turn.

There's unfortunately some tension between the +2 and the ultimate, as if things are going well (or really badly) you may not be able to use the +2, but I decided if things are going well enough, you may be happy to activate the +2 for nothing, and if things are going badly, you probably need the -1. There's still the problem that you don't especially want to return cards to your hand before casting your ultimate, but it does let you trade off more freely. I'm not sure.

Originally the ultimate was the same as Varlan the Grower, since "Copy every creature you have in play" is a good win for an ally deck. But I decided that you wanted something that would give you a second wind, not something that would crush defeated opposition, so it lets you dump all the ally cards you've drawn onto the table whether you've played them or not. That ought to be enough to win. (You could also do "X copies of target creature", which has less memory issues, but I decided "play all" would feel more satisfying if you'd been holding something you couldn't play)

There's still the problem you can't tutor up specific allies to answer a problem.

I don't really find that that there's tension between the two, they just sort of cover the same territory. I mean, you can still play the Allies you returned with the +2 by using the ultimate. I'm curious as to why you chose the creature, size, and color you did for the -1. Why not just make it Join the Ranks?

Hm. At first I didn't like the pairing of the +2 and the ultimate, but on second thoughts it's fine because the ultimate lets you cast the ones you've brought back and not cast. I think 4/+2/-7 is the right spot for those loyalties - 1 turn after you cast him would be possibly too good, but 2 turns after you cast him feels like it ought to leave him alive afterwards.

L2i0n0k7: Hm, thank you, good point. I instinctively wanted to do something different, but "cast the most iconic spell for the ability" is traditional planeswalker advice, so maybe it should.

Alex: Thanks. Yeah, I'm not experienced at costing planeswalker abilities, but these felt a reasonable combination.

Yeah, you're not losing anything by using the [+2] if you then lose the ultimate, but not gaining much either is what made me hesitate.

I may or may not do a Mk II set of three.

I also feel like the colorless aspect of the Beast is rather strange, and evocative of the Eldrazi.