It seems I'm not the only DM/player surprised that many of the outlier 2014 spells were not revised or balanced in the new PHB.

This is my take on revising the Heat Metal spell, inspired by the 3rd edition version of the spell. The "dual concentration" mechanic is a house rule, a game mechanic I apply to some spells when I revise them for my players (e.g. hunter's mark). 

Let me know what you think of this revised version. Amounts to about 40 Fire damage on average (9d8) over 4-5 rounds. No save, but various ways to offset the damage. 

Choose a manufactured metal object, such as a metal weapon or a suit of Heavy or Medium metal armor, or a Construct made of metal that you can see within range. You make the object or Construct gradually warmer until it glows red-hot. Any creature in physical contact with the object (or the Construct itself) takes 1d8 Fire damage when you cast the spell. 

A creature holding a heated object that takes damage from it must succeed on a Constitution saving throw or drop the object (it can choose to drop it). If the object is a weapon, the creature has Disadvantage on attack rolls while holding it because of the pain.

At the start of each of its turns, the Construct and/or a creature in physical contact with the object or Construct (if the Construct is grappling them, for example) takes Fire damage as shown on the table below.

If the object or creature takes at least 15 Cold damage from a single source, the Fire damage on the creature's next turn is halved. A creature that gets soaked with heavy rain or at least 8 pints of water (two full waterskins) gains Resistance to the Fire damage from this spell. (The creature or one of its allies must take the Utilize action to empty a waterskin.)

A creature wearing metal armor can choose to remove it quickly by damaging it: 2 actions are required for chain shirts and chain mail (cutting the leather straps, then bowing deeply and sliding the chain over one's head), or 3 actions for half plate, full plate, and breast plate (breaking off metal clamps, loosening the gambeson underneath it, removing the pieces)...  The damaged armor must be repaired before it can be worn again.

Dual concentration. You can concentrate on this spell or another spell or effect, but if you lose your concentration, you lose both effects.

Using a Higher-Level Spell Slot. You can target an additional object or creature for each spell slot level above 2nd.

Why do you think this is necessary? in 2024 Heat Metal is not a problem because it requires both concentration and the caster to remain within range to reactivate the damage. This means the most effective way to overcome it is for the victim to charge the caster and attack them to cause them to drop concentration. 

Heat Metal is a significantly weaker spell than Spiritual Weapon, why do you think it requires additional nerfs?

Quote from Agilemind >>

Why do you think this is necessary? in 2024 Heat Metal is not a problem because it requires both concentration and the caster to remain within range to reactivate the damage. This means the most effective way to overcome it is for the victim to charge the caster and attack them to cause them to drop concentration. 

Heat Metal is a significantly weaker spell than Spiritual Weapon, why do you think it requires additional nerfs?

 I've seen it used in some games where the Heavy armor wearing creature is affected and unable to break the caster's concentration for various reasons (War Caster feat, caster flying or invisible, unreachable for x reason, etc.)... Someone can not simply drop a heavy wearor it's wearing and takes several minutes to doff. Thus, with the appropriate set up, you can deal up to 20d8 damage (90 average) to a single creature over 1 minute.  I've seen it abused. Spiritual Weapon did get a nerf in the new PHB as well, now requiring concentration.

Quote from Benz74M >>

Quote from Agilemind >>

Why do you think this is necessary? in 2024 Heat Metal is not a problem because it requires both concentration and the caster to remain within range to reactivate the damage. This means the most effective way to overcome it is for the victim to charge the caster and attack them to cause them to drop concentration. 

Heat Metal is a significantly weaker spell than Spiritual Weapon, why do you think it requires additional nerfs?

 I've seen it used in some games where the Heavy armor wearing creature is affected and unable to break the caster's concentration for various reasons (War Caster feat, caster flying or invisible, unreachable for x reason, etc.)... Someone can not simply drop a heavy wearor it's wearing and takes several minutes to doff. Thus, with the appropriate set up, you can deal up to 20d8 damage (90 average) to a single creature over 1 minute.  I've seen it abused. Spiritual Weapon did get a nerf in the new PHB as well, now requiring concentration.

 Even requiring concentration, Spiritual Weapon is still better than Heat Metal - more reliable damage type, can be moved between different targets, can attack any creature not just one wearing heavy armour. 

Yes, heat metal is powerful against a creature wearing heavy armour but that's the trade off from being completely useless against any creature that is not wearing or holding a metal weapon/heavy armour - which is the vast majority of creatures. Warcaster doesn't prevent a creature losing concentration at best it let's the hold it ~2-3 extra rounds. Invisibility =/= undetectable a creature can absolutely find them and attack them, STR creatures can throw weapons at flying casters, or move to reach them - climb up walls, push through doors etcs... With the 2024 version of Heat Metal the caster can't even move away from the target - they have to stay within 30 ft (aka Javelin throwing distance). 

If the enemy is in a situation where Heat Metal can do 90 damage to them (even using the old version), then the druid could equally auto-kill them just by using a longbow to shoot them. I've been DMing for 3 years with always a druid in my party and I've never ever seen them pull off this supposed "abuse" of Heat Metal. I've seen Paladins get annoyed by being hit by Heat Metal in PvP and having to chase around and throw javelins at the druid but they always manage to break the druid's concentration before the Paladin dies. 

TL:DR if your encounter design is such that it can be cheesed by Heat Metal, it could equally be cheesed by anyone with a bow / crossbow or other ranged attack, so the problem isn't Heat Metal the problem is your encounter design.

PS: I also played a Druid in a campaign for 2 years, and I stopped preparing heat metal halfway through because in 75% of combats there were no enemies with anything metal on them, and enemies with metal armour occurred in only 10% of combats or fewer. In another campaign I was DMing I allowed the players to do the : one person sticks a metal weapon into an enemy then the druid casts Heat Metal on it because otherwise there was almost no opportunity for the druid to use Heat Metal.

I hear you, and you make 

Quote from Agilemind >>

Quote from Benz74M >>

Quote from Agilemind >>

Why do you think this is necessary? in 2024 Heat Metal is not a problem because it requires both concentration and the caster to remain within range to reactivate the damage. This means the most effective way to overcome it is for the victim to charge the caster and attack them to cause them to drop concentration. 

Heat Metal is a significantly weaker spell than Spiritual Weapon, why do you think it requires additional nerfs?

 I've seen it used in some games where the Heavy armor wearing creature is affected and unable to break the caster's concentration for various reasons (War Caster feat, caster flying or invisible, unreachable for x reason, etc.)... Someone can not simply drop a heavy wearor it's wearing and takes several minutes to doff. Thus, with the appropriate set up, you can deal up to 20d8 damage (90 average) to a single creature over 1 minute.  I've seen it abused. Spiritual Weapon did get a nerf in the new PHB as well, now requiring concentration.

 Even requiring concentration, Spiritual Weapon is still better than Heat Metal - more reliable damage type, can be moved between different targets, can attack any creature not just one wearing heavy armour. 

 

(...) 

TL:DR if your encounter design is such that it can be cheesed by Heat Metal, it could equally be cheesed by anyone with a bow / crossbow or other ranged attack, so the problem isn't Heat Metal the problem is your encounter design.

PS: I also played a Druid in a campaign for 2 years, and I stopped preparing heat metal halfway through because in 75% of combats there were no enemies with anything metal on them, and enemies with metal armour occurred in only 10% of combats or fewer. In another campaign I was DMing I allowed the players to do the : one person sticks a metal weapon into an enemy then the druid casts Heat Metal on it because otherwise there was almost no opportunity for the druid to use Heat Metal.

I hear you and you make very good points. I could indeed use the version as written and simply have targets try to disrupt concentration.

However, you're so good at convincing me that Heat Metal RAW isn't that strong that I now think my revised 3rd-edition version might actually be an improvement :)  60 feet range, can target a Construct made of metal (so if you know you'll be fighting metal constucts, it becomes a good spell to prepare), no need to use Bonus Action to keep the heat, dual concentration in order to use another concentration spell at the same time...  But with 3rd edition's flavorful ways to limit the damage with Cold damage or water.