A Look Back at Training Grounds in cEDH

Training Grounds by Caroline Gariba
cEDH is absolutely full of card advantage engines nowadays. You've got your classic blue staples, like Mystic Remora
These are all excellent value engines on their own, but if you're fortunate enough to be playing Thrasios, Triton Hero
A Look at Thrasios
Before getting into the nitty-gritty of Training Grounds
For two mana - - Thrasios offers you a 1/3 legendary Merfolk Wizard creature with partner and the activated ability ": Scry 1, then reveal the top card of your library. If it is a land card, put it onto the battlefield tapped. Otherwise, draw a card." This might not sound like much at first glance, but then again neither does the zero-mana Kobold Rograkh, Son of Rohgahh
First, the mana cost. Providing both blue and green to your deck's color identity while also only costing two mana means that Thrasios can realistically be deployed as early as turn one and immediately start contributing to the commander-dependent cards that hover around cEDH tables, such as Fierce Guardianship
Moving next to the actual activated ability which Thrasios provides access to, let's first look at it by face value and then see how we can really use this in the cEDH context. As for the "fair" version, four mana per card is an absolutely abysmal rate. I jam just about every value engine I can get my hands on in my stax lists, and even in those lists I wouldn't run a creature just because it had ": Draw a card" on it. Sure, there's value in the ability to activate it over and over again on players' endsteps as the game goes ever longer, but this isn't the kind of value to write home about. Rather, the potential here comes from the broader meta context against which Thrasios competes; that is, cEDH is a format full of infinite mana combos, and Thrasios is here to put all of that mana to use. Yes, you'll likely toss around an activation of Thrasios here or there in the middling turns of a game, but make no mistake: Thrasios is among the truest champions of the infinite mana gameplan.
Did somebody say infinite mana?
Understanding Training Grounds
So, now that we have the gist behind Thrasios, what is Training Grounds
In short, I think it is, or at least it is for some Thrasios lists. Green is already the color of explosive-yet-dependable mana acceleration via things like mana dorks and Gaea's Cradle
When Thrasios costs to activate, the rate at which it puts lands into play is just too slow to meaningfully accelerate the average number of possible activations per turn cycle. However, with Training Grounds
Now, I do have to yield that Training Grounds
What Lists Want Training Grounds
Partner Option One - Rograkh, Son of Rohgahh
Overall, the number one deck that I think can gain from running Training Grounds
Now that's a lot of mana.
While it might seem odd to toss in a slow value engine into a list that can play blisteringly fast, it is actually this consistent-yet-explosive mana package that makes Training Grounds so good here. Making this much mana means that, on the turns when you aren't gunning for a win, you can just sink all those extra resources straight into Thrasios and either ramp even harder for next turn or draw into threats for another win attempt. This list pushes non-infinte mana to its limits (up until it decides it's time to actually make infinite mana, that is), and as such really makes the most out of Thrasios. Training Grounds just happens to be the commander-dependent version of this maximization, so while it won't directly make you more mana or draw you more cards it most certainly will be helping your commander to get you there.
Partner Option Two - Tymna, the Weaver
This list takes the opposite approach as the Rograkh, Son of Rohgahh pairing and, instead of maximizing the amount of mana we can invest in Thrasios, offers to maximize the amount of time we play with the commander out instead. Unless you're rushing towards an early Thassa's Oracle combo, trading out red for white and black in your color identity will almost always assure you a slower game, one which will offer you plenty more untap steps from which you can draw newly rejuvenated mana for your Thrasios activations.
Now, while Thrasios can certainly take advantage of a slower game, the reason I chose to put this list below that of Rograkh, Son of Rohgahh is that, when circumstances require, that list can play to a slower tune, as well. Sure, swapping out colors incentivizes a different play pattern, but that doesn't mean its mutually exclusive. What is much harder to pivot, however, is the rate at which a list provides its player with real resources - ie mana - and so, while Rog Thrasios can play a slower game but keep faster mana, Tymna Thrasios can't do the same. This will inevitably cut into the number of cards drawn off of a Training Grounds-support Tymna Thrasios list, in comparison to Rog Thrasios, but not sufficiently so as to disqualify it from favourable consideration.
What Lists Don't Want Training Grounds
Partner Option Three - Bruse Tarl, Boorish Herder
Moving away from our favourable options and into the Thrasios lists that don't want Training Grounds, there is really only one option that comes to mind which is both popular competitively and decidedly against Training Grounds: Bruse Tarl, Boorish Herder. Why, you ask? Well, that's because this list is already playing a copy of Training Grounds, albeit by another name: Zirda, the Dawnwaker.
Bruse Thrasios keeps much of the fast mana from other red lists (albeit missing the aforementioned Rograkh-synergy pile) plus is able to play a bit more flexibly thanks to the interaction suite and additional card advantage options provided by white (Silence, Esper Sentinel, etc), and as such is all around an excellent deck when it comes to considering the effect which Training Grounds offers. However, Zirda, the Dawnwaker - a red and white creature which only this version of Thrasios is allowed to play - has this same effect and then some, affecting not just creatures but all non-mana activated abilities of permanents you control. Zirda may cost three mana instead of one, but that additional investment also gets you a card that combos with the likes of Grim Monolith and Basalt Monolith, adding infinite mana which - thanks to Thrasios - you can easily convert into a win. Training Grounds is good, but it isn't Zirda levels of good.
Wrap Up
It might not be Mystic Remora, but something tells me that this one-mana blue enchantment has a strong future in Thrasios lists far and wide. cEDH is a game of mana efficiency, and while two mana per activation isn't insignificant, it sure is a whole lot better than four, especially when it pays for half of the cost via a new land in play every now and again. So, for all the Thrasios, Triton Hero players out there (that aren't playing Bruse), give Training Grounds a shot. The format's slowed a good bit since we last looked over this card, and decks are making more mana than ever, so why not take those untapped lands and put them to use?