Originally Posted by Buba68
Thank you, @RedQueen and @Blackheifer.
I am now trying to wrap my mind about those rules - Thorn Whip is a Melee Attack? - 5ed is hard!

Ha, it helps to think in terms of what is your melee spell attack and what is your ranged spell attack for tactical purposes.

For example:

Druids

Your Melee Spell Attack is Thorn Whip/ Your Ranged spell attack is Produce Flame

Clerics:
(skipping cantrips because they are underpowered and not really worth using)

Your Melee Spell Attack is Inflict Wounds/ Your Ranged Spell attack is Guiding Bolt

Wizards/Sorcerers:

Your Melee Spell attack is Shocking Grasp* / Your Ranged Spell Attack is Flame Bolt/Chill Touch/ Freezing Ray

The key is - as Niara and MrFuji3 mentioned - that ranged attacks are at Disadvantage when you have an enemy within 5 feet. So you either need to move away to use a ranged attack or switch to a melee Spell Attack.

* Shocking Grasp is an absolutely essential spell and it's criminal that it isn't a default choice. It's melee range spell attack. Does 1d8 electrical damage, Advantage against opponents with metal armor, it removes the enemy reaction so you can run away without an opportunity attack, it can be used to electrify water surfaces. Just, incredibly useful spell.

p.s. I need to mention that Magic Missile is a ranged spell but there is no attack associated with it, so it can be used at close or far range without penalty. Really the best spell for breaking concentration in enemy spellcasters.

p.p.s. - Having spent years with 2.5e and 3.5e I can say that 5e is the best D&D system ever developed. It makes the game so much easier to play by simplifying so much. 3.5e was a nightmare to DM as you had to look up so many special conditions that would influence dice rolls and it led to a lot of bickering if you missed one of the special conditions after a turn had passed. It's a lot more flexible as well, giving players a lot more agency to create their own subclasses and hombrews.

Blackheifer