Rules-changing static abilities
Many Planeswalkers in the set have rules-changing passive abilities that restrict the actions of the other player (Angrath, Ashiok, Dovin, Karn, Kasmina, Narset, Tamiyo, Teferi, Teyo, Tibalt). Most of them are playable in Limited, and some are seeing heavy play in Constructed, even in older formats.
There are some concerns that these abilities could be the cause of many GRV or HCE Warnings, with unfortunate consequences on game enjoyability, sportsmanship, and even tournament integrity.
The first Competitive Standard tournaments showed a significant number of planeswalker-related Warnings, but not to an alarming extent. We are monitoring the situation and discussing various options but, at this point, we do not feel this issue requires a specific fix.
We encourage Head Judges to remind players to be careful about the static abilities of their opponent’s planeswalker.
Snow-covered basic lands
Modern Horizons brought snow in June, and with it some full-art snow basic lands with gorgeous art. It is likely that some newer players will try to use these lands in Standard or in non-Modern Horizons Limited events.
They are not legal in these formats, so their decks are technically illegal. As there is every chance that it is noticed by a Judge, or when the card becomes visible to their opponent, the penalty should be a Game Loss. However, since there is no way of abuse in playing a snow land in these formats, we recommend downgrading this penalty to a Warning and replacing the lands with non-snow versions.
Note that listing non-snow basic lands and playing snow basic lands (and vice-versa) in older formats such as Modern, or using snow basic lands that were not part of the player’s pool in Modern Horizons Limited is still a Game Loss. Note that in that last case, you probably want to investigate for Cheating.
If a player draws before announcing or physically proliferating, they chose to not proliferate any permanent.
As they drew a card, they had access to new information, so the Reversing Decisions section of the Magic Tournament Rules (MTR 4.8) cannot apply.
Out-of-Order Sequencing (MTR 4.3) may apply if everything happened in a single motion and you believe that the intent of the player is obvious.
Note that there are many cards that can affect the choice of which permanents to proliferate, especially in Limited: Duskmantle Operative and The Wanderer are obvious suspects, but there are many other cards or combinations of cards that can be contextually pertinent. Generally, if you suspect that “Proliferate all my things and none of yours” is not obvious, this should be a strong hint that Out-of-Order sequencing is not appropriate.
It is not necessary to physically add the counters before drawing as long as the player’s intent is clear: “Proliferate my two creatures”, draw, physically add counters is fine.
Burning Prophet has a single triggered ability that does two things: One is a physical action (Scry), the other is non-visible (+1/+0).
If its controller forgets to scry upon casting a non-creature spell, this does not mean that the trigger is entirely “missed” in the sense of IPG 2.1. Indeed, as per MTR 4.2, the game considers that they scried to the top. They can therefore still benefit from the +1/+0 part if they demonstrate awareness about the power increase before it has an impact on the visible game state.
Feather, the Redeemed & Ugin, the Ineffable
These two cards have abilities that move a card from a zone to another and set up a delayed trigger that moves this card to a third zone. This does not match exactly the new template for the zone-change fix of Missed Trigger, but they are handled in the same way: these triggers do not expire and are always resolved when they are noticed, either the next time a player gets priority or when a player would get priority at the start of the next phase.
The wording of the IPG will be updated in a future release.