Solemnity
Oracle Text
Players can't get counters.
Counters can't be put on artifacts, creatures, enchantments, or lands.
Card Rulings
7/14/2017 Solemnity doesn’t remove any counters players or permanents already have.
7/14/2017 Solemnity stops counters from being put on an artifact, creature, enchantment, or land as it enters the battlefield, as well as stopping counters from being put on them later.
7/14/2017 If the cost of an ability or an additional cost of a spell requires putting counters on an artifact, creature, enchantment, or land, that cost can’t be paid. If a resolving spell or ability says that a player may put counters on one of those objects, that player can’t choose to do so.
7/14/2017 If a replacement effect allows a player to modify or replace an event by putting counters on an artifact, creature, enchantment, or land, that player may apply that replacement effect. Counters won’t be put on the object, but if the original event is entirely replaced (such as by applying Soul-Scar Mage’s replacement effect), the original event won’t happen.
7/14/2017 If an artifact, creature, enchantment, or land would enter the battlefield with counters on it at the same time that Solemnity enters the battlefield, Solemnity doesn’t stop it from getting those counters.
7/14/2017 Damage from a source with wither has no effect on creatures. No -1/-1 counters are put on them, and no damage is marked on them. The damage is still dealt for purposes of effects that care about damage, such as lifelink.
7/14/2017 Damage from a source with infect has no effect on creatures or players. No -1/-1 counters are put on creatures, and no damage is marked on them. Players don’t get poison counters and they don’t lose life. The damage is still dealt for purposes of effects that care about damage, such as lifelink.
7/14/2017 Counters can be put on cards that aren't on the battlefield. Notably, suspended cards will still get time counters.
7/14/2017 If a creature with tribute is entering the battlefield, the chosen opponent can’t pay tribute even if they want to.
7/14/2017 While resolving a cumulative upkeep trigger of a permanent, you’ll fail to put a counter on that permanent, then you may pay for the age counters already on it. If it has no age counters on it, you may pay .
Also Rip Hapatra Decks.
And Soul Scar Mage.
With everything else, the card must explicitly state that the effect affects Planeswalker, hence why cards like Sandwurm Convergence state "You or Planeswalkers you control."
Because this card does not involve damage of any kind & does not mention Planeswalkers at all, this card does not affect them in any way, though if you somehow manage to make a Planeswalker a creature & then attempt to put a loyalty counter on it, it would not happen.
The only difference is that if it says "Planeswalker" you cant target a normal player.
All planeswalkers are Players but Players arent Planeswalkers (Except in the lore)
Planeswalkers are a type of permanent card, not a player. T_T
This is kinda funny cause the only real way to kill to gods, besides exile, is -1/-1 counters. This prevents that from happening.
Also, Phyrexian Unlife with this card is hilarious.
Yeah, Phyrexian Unlife + this could see modern play in prison builds as a soft lock/aggro killer.
EDIT: vanishing rules... I'm incorrect here. when a permanent with vanishing has zero time counters, it has a triggered ability to sacrifice it.
the upkeep trigger is a separate part. vanishing is technically 3 abilities/effects all bound together.
if it enters with zero, it immediately triggers a sac trigger.
chrono played after this is instant infinite copies, breakable only by removing the enchantment.