Planar Binding

[VoxRationis]

So apparently planar binding requires additional spells to work in this edition (besides the magic circle spell). What methods is one supposed to use to make this work? If one simply uses the regular summoning spells, it seems like a lot of effort just to increase the duration (unless one is so high-level that the planar binding spell works for a week—at which point the intended use of the spell is beyond the reach of a wizard when they're first able to cast it) of an existing spell.

[MaxWilson]

So apparently planar binding requires additional spells to work in this edition (besides the magic circle spell). What methods is one supposed to use to make this work? If one simply uses the regular summoning spells, it seems like a lot of effort just to increase the duration (unless one is so high-level that the planar binding spell works for a week—at which point the intended use of the spell is beyond the reach of a wizard when they're first able to cast it) of an existing spell.

It's mostly for the higher-level slots, but even the basic 5th level version lets you have an elemental, for example, which will not turn on you when you lose concentration.

Planar Binding can let you have two Earth Elementals at 9th level (because Arcane Recovery), or an Earth Elemental inside of a Stinking Cloud (extremely strong due to poison immunity, and tremorsense for advantage on attacks/disadvantage on opponents' attacks). Not nearly as good as having an Earth Elemental for a week or a month, but not bad either if you're sufficiently wealthy.

If your campaigns are sufficiently easy (Combat As Sport) that may not be necessary/desirable, but if you're trying to tackle something which could kill you in a straightforward fight (Combat As War), you want to stack the deck in your favor as much as possible. When it's time to invade the Mind Flayer underground caverns you will want as much firepower on your side as you can get. (Just make sure the elemental watches out for Intellect Devourers.)

[Mara]

So apparently planar binding requires additional spells to work in this edition (besides the magic circle spell). What methods is one supposed to use to make this work? If one simply uses the regular summoning spells, it seems like a lot of effort just to increase the duration (unless one is so high-level that the planar binding spell works for a week—at which point the intended use of the spell is beyond the reach of a wizard when they're first able to cast it) of an existing spell.

It changes the duration not increases it. This is very different because it removes the concentration mechanic.
1. Magic Circle
2. Summon
3. Loose concentration on spell, summon now monster remains trapped in circle
4. Planar binding

or

1. Magic Circle
2. Lure outsider to circle
3. Bind trapped outsider

Interestingly druids have trouble using planar binding unless they get magic circle (via land I think?)

[MaxWilson]

It changes the duration not increases it. This is very different because it removes the concentration mechanic.
1. Magic Circle
2. Summon
3. Loose concentration on spell, summon now monster remains trapped in circle
4. Planar binding

or

1. Magic Circle
2. Lure outsider to circle
3. Bind trapped outsider

Interestingly druids have trouble using planar binding unless they get magic circle (via land I think?)

Or just have two separate druids so you don't need Magic Circle.