There are always a few ways to implement something for MTG Arena, and each new set brings another wave of tricky and interesting cards to consider. MTG Arena card set designer Jeremy Bower shares details about some of the mechanics and cards you should know about when playing with Strixhaven: School of Magic on MTG Arena on April 15!

Mechanics

Learn and Lesson

The learn action lets you either put a Lesson card from your sideboard into your hand or discard a card in your hand to draw. Of course, you can always ignore your teacher and do neither; learning is optional.

Provided you have Lessons in your sideboard to get and cards in your hand to discard, MTG Arena will present both to you when learning. Just select the Lesson you want or toggle to your hand to choose a card to discard if you'd rather draw.
In Booster Draft, you'll have access to any Lessons you drafted but didn't put in your deck. In Sealed Deck, you'll have access to any Lessons you opened but didn't put in your deck. In Best-of-One Constructed formats, you'll only have access to the first seven cards of your sideboard. Any Lessons not in those first seven cards will not be available when learning.

Magecraft

The students and faculty of Strixhaven have magecraft abilities that trigger whenever you cast or copy an instant or sorcery spell.

Ward

Your opponent's creatures with ward counter your spells and abilities that target them unless you pay the ward cost.

Like hexproof and protection, ward displays unique protective sigils on what it protects.
MTG Arena asks you for confirmation whenever you select a target with ward to give you a chance to confirm you are going to be willing to pay the ward cost.

Card-Specific Notes

Accomplished Alchemist and Pestilent Cauldron

These two Witherbloom cards have count badges to track how much life you've gained this turn.

Channel (Mystical Archive)

After casting Channel, click the Channel effect that appears on the left of the screen to manually add mana. Be careful though—it will hurt!
After casting Channel, if the only Auto Tap solution involves using the effect, you can click Auto Pay and let Auto Tap do the rest.

Fractals (Serpentine Curve and friends)

Most of the cards that create Fractal tokens have a Fractal count badge that display how many counters they are expected to put on that token. For example, Leyline Invocation's count is the number of lands you control, and Serpentine Curve includes the +1.
The Fractal count on Emergent Sequence displays how many lands you had enter the battlefield this turn so far! That's likely to change when the spell resolves.
The Fractal count on Manifestation Sage shows how many cards are currently in your hand. As soon as you cast it from your hand, that number goes down.
Fractal Summoning and Kasmina, Enigma Sage have X costs, so the X value on the stack takes the place of a count badge.
Biomathematician has no count, as it only puts one counter on each of your Fractals. That's as easy as Quandrix math gets.

Mastery Cycle (Baleful Mastery and friends)

To pay the alternate (cheaper) cost, choose the right option while casting this spell, "Cast with alternate cost."
On the stack, the text "student cost paid" will let you know if the opponent paid the alternate cost. If it's not present, they paid full price.

Storm (Mind's Desire and friends, from the Mystical Archive)

Mind's Desire and other cards with Storm have a count badge in your hand so you know the current "storm count." The storm trigger on the stack will also have a count so both players know how many copies are going to be made if they want to respond.

Snarl Cycle (Furycalm Snarl and friends)

The play highlight on the Snarl cycle of dual lands is the normal bright blue when you have another land of the appropriate type to reveal. That highlight changes to a yellow warning color when you don't have the correct land to reveal, and it will enter tapped.

Tezzeret's Gambit (Mystical Archive)

When casting Tezzeret's Gambit, you will be prompted to choose how to pay for the Phyrexian blue mana. Toggle to the Phyrexian symbol if you want to pay 2 life.

Uvilda, Dean of Perfection

You can quickly see how many hone counters are left on the exiled cards by looking at their tracker on the left side of the screen.

Closing Statement

You will automatically stop during your end step if you can afford to cast this spell during your end step and you have a legal target.
If you don't plan on casting this spell during your end step, you can select "Pass Turn" earlier in the turn to avoid the extra stop.