With every new expert level expansion, Wizards of the Coast explores the invention of new keyword abilities and mechanics. Aetherdrift was no exception--the racing set brings us new and returning abilities to explore. Speed and Start Your Engines are a brand new pair of keywords that kind of remind me of the ring tempting from The Lord of the Rings. There are new vehicles, mounts and saddling, and deciduous keywords like cycling.

There's also an ability in Aetherdrift that existed in some shape or form in the past, but now has a keyword to describe it for convenience: Exhaust. It sounds like an ability related to racecars, but it isn't exactly related to automobile pollution. Instead, Exhaust gives a familiar ability a refresh.

What Is Exhaust?

According to Wizards of the Coast's website, Exhaust is akin to putting the "pedal to the metal." You can activate an Exhaust ability to give a little extra gas to your card, but it can only be used once. Let's look at an example with Prowcatcher Specialist:

This is a fairly basic red common creature with haste, not aggressively costed or overly impressive on its own. However, a little later in the game, you have the option of paying four mana to put two +1/+1 counters on Prowcatcher Specialist, upgrading its stats and scaling with the game. Now instead of being a largely unimpactful card late in the game, you have a creature that gets a little extra reach for four mana.

Note the reminder text after the Exhaust ability is described on the card: "Activate each exhaust ability only once."

Not all Exhaust cards involve +1/+1 counters, although this seems to be a popular choice by Wizards. If every Exhaust keyword placed +1/+1 counters on the creature, Wizards may as well just call the ability Monstrosity, because that's effectively what it would be. Instead, there are a number of different Exhaust abilities you'll find throughout Aetherdrift, sometimes not even on creatures! For example, Stampeding Scurryfoot is a 1/1 one-drop creature with an Exhaust ability that adds a +1/+1 counter and creates a 3/3 Green Elephant creature token.

This ability is a great way to print cards that have relevance in both the early stages and middle / late stages of a game. The fact that these abilities can only be used once means Wizards of the Coast has a little flexibility of juicing the power level a bit, since there would be no way to abuse the ability repeatedly.

That's not to say shenanigans aren't possible, mind you. For example, you could activate Stampeding Scurryfoot's Exhaust ability to create a 3/3 Elephant, then find a way to blink or bounce the mouse. When it comes back into play, it's a brand-new copy of Stampeding Scurryfoot, meaning its Exhaust ability can be activated again...even if you already have the first 3/3 Elephant token in play!

I also appreciate that Exhaust doesn't limit you to "activating only as a sorcery" as I feared it might. Granting you the option of activating these powerful abilities at instant speed leads to much more dynamic and interesting gameplay, and I'm confident Exhaust will have a positive impact on Aetherdrift Limited. My only complaint about Exhaust is having to track usage of the ability. Since it can only be used once, you will have circumstances where you may activate a card's Exhaust ability, and then find yourself ten turns later forgetting if you've activated the ability or not. This gets especially complicated when you have multiple cards with Exhaust and even multiple copies of the same card with Exhaust.

Wizards of the Coast recommends a special token or counter to place on cards once their Exhaust ability has been used. I suspect there will be an official "Exhaust" piece that comes with Bundles, reminiscent of the locked door demarcation from Duskmourn. Whatever you use, I'd strongly encourage you track this closely, especially when playing in competitive Limited Aetherdrift events where these are bound to see play.

Other Exhaust Cards

Let's take a quick look at some more Aetherdrift cards with the Exhaust keyword to appreciate the full breadth of the mechanic. Check out Boom Scholar, a Gruul signpost uncommon that packs a real punch!

Not only does Boom Scholar itself have a powerful Exhaust ability, it also reduces the cost of Exhaust abilities of other permanents you control by two mana! Thus, the Red / Green deck in Limited appears to be centered around Exhaust abilities. Six mana is a steep cost to pay, but granting trample to your team until the end of turn and giving all your creatures (and vehicles) a buff is nothing to sneeze at! It's almost like a mini Overrun tacked onto a creature that you can activate at instant speed. Imagine having these in multiples...

There are Exhaust cards printed at higher rarities as well. Take a look at Loot, the Pathfinder, a mythic rare creature from Aetherdrift.

That casting cost is a bit prohibitive, but a 2/4 Double Strike, Vigilance, and Haste stat line is quite powerful. The real power, however, comes in the form of Loot's three Exhaust abilities. That's right, you have three abilities that you can use one time each! For Green mana, you get a Black Lotus activation; for a Blue mana, you get to Ancestral Recall; for one Red mana, you get to Lightning Bolt something. I love this playful throwback to Limited Edition Alpha cards stapled onto Loot, the Pathfinder. It's just a shame there wasn't a Time Walk or TImetwister activation include...I guess that may have been a bit too powerful.

It appears Gruul isn't the only two-colored combination that gets a signpost Exhaust card. Simic also has its share of the ability, such as Skyserpent Seeker.

A 1/1 flying, deathtouch creature can be a bit of a nuisance to attack through. Then you add on a four mana Exhaust ability (interestingly, a colorless Exhaust cost) to ramp you two lands and add a +1/+1 counter to Skyserpent Seeker, and you have a formidable Magic card! I especially like how the card gets you any two lands and not just basic lands. I wonder if this card will see some constructed play in a ramp deck of sorts.

Then there's the Simic Rare, Sita Varma, Masked Racer, a legendary human rogue creature with a powerful Exhaust ability. In this example, the Exhaust activation has an X in the casting cost. Not only does Sita Varma, Masked Racer have both early game and late game relevance, its ability also scales with the game completely. The longer you wait to activate the Exhaust effect, the bigger the effect will be. The pump effect is nice, but giving all your other creatures base power and toughness equal to some ungodly high value seems like an awesome win condition to try in Limited.

Finally, let's look at a Vehicle with the Exhaust keyword: Marshals' Pathcruiser is an interesting one!

A three-mana 6/5 Vehicle?! That would be powerful, except that crew cost of 5 is hugely prohibitive. Fortunately, the card does help you fix your mana by fetching you up a basic land, so it isn't a complete brick in the early game. Then if you somehow manage to assemble the mana, you can permanently turn Marshals' Pathcruiser into an 8/7 creature! I don't think this will be all that good in Limited, but I guarantee someone will pull it off and earn all sorts of screen shot street credit.

Wrapping It Up: The More Things Change...

Before concluding, I want to share an observation regarding the Exhaust keyword. While it's nice to have a single word to describe the "activate this ability only once" text, I must say that Aetherdrift didn't debut this effect. Mild-Mannered Librarian, from Foundations, essentially had an Exhaust activated ability for four mana (though it didn't have to tap).

Commander 2018 introduced a card with an activated ability that could only be used once, six years prior to Mild-Mannered Librarian. Can you guess the card? I would never have found it if not for my Gatherer search--the card is called Emissary of Grudges.

With this creature, the activated ability doesn't involve mana or tapping. All you have to do to use its effect is revealing the player you secretly chose when Emissary of Grudges entered the battlefield. Reading the effect, it makes sense to limit this creature to just one activation. This effectively makes Emissary of Grudges [one of] the first cards with an Exhaust ability!

Thus, the more things changes, the more they stay the same. It's not novel to grant a card some ability that's only usable once. Giving such an effect a keyword, however, that makes the game a little easier to understand is a net positive for Magic. It takes a little getting used to, but I love when Wizards of the Coast provides us with these helpful one-word shortcuts. Exhaust wasn't the first and it certainly won't be the last. Thanks to Aetherdrift, we will be seeing this kind of ability much more for the next couple months!