Progress is mostly the product of rogues (Tom Peters)

I have a Rogues Kindred Commander deck. That's not surprising, really, because I have a lot of Commander decks. But I also have a Rogues Kindred 60-card casual deck. I really like them.

Many a man would have turned rogue if he knew how (William Hazlitt)

Aside from being cool, Rogues come with a Kindred ability called Prowl. It is an alternative cost which shows up on a total of 11 cards, though one of them works differently than the other 10. Aside from the one... ahem, rogue... card, they're all in either Black or Blue, which makes sense, because that's the color pair of the Rogue type from Morningtide, when our story begins.

I think the greatest rogues are they who talk most of their honesty (Anthony Trollope)

Cards with Prowl may be cast for their Prowl cost if "a player was dealt combat damage this turn by a source that, at the time it dealt that damage, was under your control and had any of this spell's creature types." (Comp. rules 702.76a)

So if you do combat damage with a Creature that shares a type with the spell with Prowl, you can cast it for its Prowl cost.

Actors are rogues and vagabonds. Or they ought to be. (Helen Mirren)

Why bother with this? As you can see from Auntie's Snitch, because sometimes you get a cost discount. Two mana is cheaper than three, right?

Morsel Theft doesn't just give you a substantial discount, it also offers you a bonus for casting it for its Prowl cost.

Notorious Throng is my favorite of all the Prowl cards; its Prowl cost is more than its normal cost, but effectively you're getting an extra turn for two mana. That's high-powered. Plus you get a free chance to attack with your newly minted flying Rogues.

There is nothing but roguery to be found in villainous men. (William Shakespeare)

These two are great examples of the power of these cards. 4 mana for a 5/5 flyer is an incredible deal. The fact it bounces each of your opponents' best things is just gravy. And Knowledge Exploitation is powerful at seven mana, but at four? Insane. Sure, I'll play this Cruel Ultimatum for four mana, thanks very much!

There is no den in the wide world to hide a rogue (Ralph Waldo Emerson)

We've got to talk about this guy.

Hailing from Jurassic World Collection, this is the only spell with Prowl which isn't a Rogue. (The others are Goblin, Faerie, and Sphinx.) It doesn't have Prowl itself, but it gives Prowl to other Dinosaurs you control. A solid addition to any Dinosaur Kindred deck; three mana is often a deal for them.

Rogue Squadron doesn't run. Unless we really, really have to. (Aaron Allston)

Let's make sure we fully understand here.

• When you cast the spell with Prowl, you look back at your turn to see if you've done what it says - dealt combat damage with a card that shares a type with the card with Prowl (so, probably a Rogue, but maybe a Dinosaur and in occasional corner cases, Goblin, Faerie, or Sphinx)
• You don't still have to control the Creature that did combat damage, you just have to have met the condition of dealing combat damage with the correctly-typed Creature.
• Prowl doesn't change timing. You still have to cast Creatures and Sorceries during your main phase. It just changes the cost.
• The reminder text is just that - the actual card types are what matter, not what the reminder text says. So, if you have a card with Prowl in your hand but something like Conspiracy has changed it into a Spirit, you must have done combat damage with a Spirit card in order to cast it for its Prowl cost.
• You don't have to cast something for its Prowl cost even if you can.
• To be completely clear, if the card says "prowl cost was paid, X", you only get X if you paid the Prowl cost.

As there is a use in medicine for poisons, so the world cannot move without rogues (Ralph Waldo Emerson)

Freerunning, a keyword introduced in (and so far only in) Universes Beyond: Assassin's Creed, is a variant of Prowl. Freerunning limits itself only to Assassins and Commanders, allowing it to be on non-permanents without the Kindred spell type.

(That is a really cool image.)

Freerunning is in every color, and even kind of has a lord in Ezio Auditore da Firenze, who gives all your Assassin spells Freerunning.

It also works identically to Prowl, except it is specifically for Assassins and can't be changed from that. So if that aforementioned Conspiracy changes your Assassin with Freerunning into a Minotaur, you can't cast your spell with Freerunning because you won't have done damage with an Assassin.

I am bewitched with the rogue's company. (William Shakespeare)

Prowl is on so few cards it can be difficult to build a deck around them; there aren't enough to be the entire theme of a Commander deck, and it's tough to imagine a 60-card deck willing to run it as a full theme. However, in the context of a Rogues Kindred deck, it's incredibly powerful. I run every legal card in my Rogues Commander deck, and I'm never sorry to see any of them. Even Thieves' Fortune and Noggin Whack are solid at that price.

Thanks for reading.