Does going outside of range or line of sight after casting a spell have any effect?

Question

Does going outside the range of the spell or breaking line of sight between the caster and target break concentration or otherwise affect control over the spell?

For example, a Heat Metal spell has a range of 60 ft. If I cast the Heat Metal spell on a an armored foe, and that foe runs outside the range of the spell (60 ft), or around the corner, does that break concentration and end the spell? Heat Metal also allows you to use a bonus action to cause the 2d8 of damage — would exercising that option be prevented by being out of range or line of sight?

Answer 1

Player's Handbook p.203

Once a spell is cast, its effects aren’t limited by its range, unless the spell’s description says otherwise.

QED

From your example, Heat Metal says:

Until the spell ends, you can use a bonus action on each of your subsequent turns to cause this damage again.

There is no range or LoS limit on this - they can run but they can't hide! Distance is not a protection and (arguably) even moving to another plane doesn't help.

Given that it takes longer to get out of armour than the spell lasts (1 minute), you had better try to break the spellcaster's concentration. Make no mistake, this is a lethal spell to use on armoured opponents especially since it scales with spell slot.

Answer 2

No. You don’t need to be within line of sight or within range to maintain concentration on a spell, unless a spell’s description or other game feature says otherwise.

The Sage Advice Rules of Spellcasting article on Wizards' site confirms this:

IF YOU’RE CONCENTRATING ON A SPELL, DO YOU NEED TO MAINTAIN LINE OF SIGHT WITH THE SPELL’S TARGET?

You don’t need to be within line of sight or within range to maintain concentration on a spell, unless a spell’s description or other game feature says otherwise.

Answer 3

To add to other answers, the description of Witch Bolt explicitly says:

The spell [...] ends if the target is ever outside the spell’s range or if it has total cover from you.

Since there's a "Specific Beats General" rule in 5e, we can conclude that this exception proves the general rule: if the caster, the target, or both move outside the range (or interfere with the lines of sight), the spell remains active.

Answer 4

There are 2 things here.

I think going outside of range shouldn't break concentration, shouldn't end the spell, BUT if the effect requires an action/bonus action to activate it then it should require sight (and/or range).

I don't think Player's Handbook p.203 is enough here.

Once a spell is cast, its effects aren’t limited by its range, unless the spell’s description says otherwise.

It only talks about range, and spells in general. Grease, Web, Alarm... shouldn't require the caster to stay in range (or have Line of Sight), but they also don't require action to keep their effects going. The important quote here is "unless the spell’s description says otherwise." It doesn't say "unless the spell’s description specifically limit the effect's range.". "says otherwise" is pretty vague. Using an action to reactivate the effect can be interpreted as "otherwise", since the effect isn't applied automatically.

The Sage Advice Rules of Spellcasting article isn't specific enough either.

You don’t need to be within line of sight or within range to maintain concentration on a spell, unless a spell’s description or other game feature says otherwise.

It does specify that PHB 203 applies for concentration spells too, and nor range nor LoS is limiting concentration. (Grease and Alarm isn't concentration spells, but Web is.)

In contrast Arcane Eye specifically says that it can be moved at any range.

As an action, you can move the eye up to 30 feet in any direction. There is no limit to how far away from you the eye can move, but it can’t enter another plane of existence.

If the general PHB 203 rule would be enough to not limit range, then why does the spell specify that the action isn't limited by range?

Neither the Heat Metal spell description nor the quoted rules above specific enough to make a definite ruling IMHO. If it didn't require any action to keep the metal heated then subsequent damage wouldn't require range or LoS, but because it does I feel it should.

(If it required an action, then at least there would be a chance to catch up with the caster, but because it's a bonus action the caster can get out of range or out of sight from even ranged opponents as well. That's just too powerful for a 2nd level spell - for the mods against the players - when the 4th level Arcane Eye requires an actual action...)