In particular,

• any Oath deck is definitely running green, but may not be able to reliably generate white mana. Even in decks running Sun Titan and a fetchable Tundra in addition to the Orchards, the Tundra competes with other color priorities (red, green).
• Beast Within can hit artifacts, enchantments, and lands. This gives you an out in circumstances that may otherwise be very awkward (surprise Leyline of Sanctity out of the opponent's sideboard, a Grafdigger's Cage or Sorcerer's Spyglass you need gone, Karakas when you are running a Legendary Oath package, an opponent's Oath in the mirror when you have lost Orchard superiority, etc).
• Beast Within can get rid of your own Oath, in the occasional and very awkward situations that it has started doing more harm than good.
• The beast is smaller and doesn't fly.

I was looking at this card more as a counterspell versuses removal, where I can turn my Mentor/Delver/Pyro into a equal threat when they go to kill it. With the side ability of removing a Tinker Bot to give you an extra turn or 2, or removing a narset/leo so you can draw cards again.

I thought Beast Within's main selling point is that it can pretty much always create a token. This can only create a token when there is already a creature in play, or there is a planeswalker in play. That seems like a pretty big limitation to me for an oath deck.

Using it on your own cards doesn't seem great either. I mean, I guess if a creature/PWer is going to be killed anyway, you can get a 2 mana 4/4 flier out of the deal. There are certainly better ways to get a value creature into play.

Using it against your opponent also seems underwhelming because leaving a leftover 4/4 flier is not a negligible threat. That can win in combat against many of Vintage's creatures, and is a significant threat to your life total / planeswalkers. There are certainly better removal.

I mean, if you are looking for a card that does all of these things, then sure it is an option, but I think you'd have be pretty tight on deck space to consider this. This is not much more than a niche Singleton.

@vaughnbros I think against the big threats in vintage I would rather have this. Also, this gets rid Blightsteel. Beast within doesn't.

@brianpk80 I think the normal use case for this card will be on your own creatures. Getting a 4/4 flier for 2 mana is really good, probably at least as good as a 5/5 non-flier for the same. But, having an artifact is easier than having a creature in Vintage, hence the prerequisite is harder.

It's got other modes too, of course. It's a counterspell of sorts too, so you have that extra mode. But if you use that mode you're not beating face. In a pinch, it's removal, but it's removal that probably puts you on a three turn clock, so not great. I like the card in general.

All good points, everyone.

If the card cost 2W, Beast Within would be better in most scenarios but the cost reduction is enormous in practice making it something I'll have to test in Oath of Druids decks that use white.

@brianpk80 MH1 printed exactly that - a 2W Beast within

@thewhitedragon69

Yea this dude.

@thewhitedragon69 yeah, the cmc is still 3.
And doesnt exile. Huge difference.

@ten-ten Yeah, but I'd rather play generous gift over angelic ascension when I'm against oath any day. A lot of decks are basically creatureless (oath, doomsday, PO storm) and this can still hit their time vault, necropotence, oath, etc., or turn your own land into a beater as a snap finisher. AA can't do any of that.

As removal, you are more able to defend against a 3/3 bear than a 4/4 flyer.

Using AA on yourself for a 4/4 flyer is basically 2-for-1ing yourself or requires some set up - which means costing 2 is less relevant. If you are trying to mutate a pyromancer token, you are netting 3 power and also likely have 3 mana. Most importantly, you need the pyromancer and a token in play. Making an elephant out of an off-color mox or a land when you've already hit your max curve is better imho. In almost all cases as a "counterspell" to get value out of a doomed PW or creature, I'd pretty much always just rather flusterstorm or something that actually saves said target.

I would imagine that deciding to play this card vs. Beast Within/Generous Gift comes down to how good your Bazaar matchup is