D&D 5E What is the best way to handle ‘magic resistance’ in D&D 5e?

[Tony Vargas]

Tentatively, attack-roll spells as an intentional method to bypass resistance, seems ok.

Doesn't scan for me (it's still magic), but this is your variant...

[/quote]Save negates is fine.

The issue is no save spells. That is where the difference with the old school magic resistance is.[/quote] Exactly. It was % check or nothing happened...
...it also applied to all magic, not just hostile (though, like so much else that'd vary with DM).

5e has the Antimagic Field spell ... at spell 8 ... and it likewise negates the magic of caster as well as the magic of any hostiles. But it is the closest 5e comes to 1e Magic Resistance.

There is also Globe of Invulnerability at spell 6, that negates spell effects according to spell level. But that mechanic feels awkward.

Those were also both classic spells distinct, mechanically, from magic resistance. The way they work is similar, while magic resistance has changed more significantly ...

 

[Yaarel]

It was % check or nothing happened...
... it also applied to all magic, not just hostile (though, like so much else that'd vary with DM).

The way my 1e group did it was, a player with magic resistance (in our case a Drow Elf) had to willingly suppress the magic resistance to receive a friendly spell, such as healing − but while doing so became vulnerable to spell ambushes.

Those were also both classic spells distinct, mechanically, from magic resistance. The way they work is similar, while magic resistance has changed more significantly ...

With regard to 5e ‘magic resistance’ as spell save advantage, I am comfortable with the Cunning-Reflex-Fortitude trio representing this in a balanced way. Its ok, yet it feels different from 1e ‘magic resistance’.

I am hoping that the ‘Spell Immunity’ spell achieves a similar feeling that sometimes a spell simply has no effect on ones own person.