Spells
Planescape includes a variety of setting-specific spells. I haven't found any 5e conversions, but many 2e spells are generally usable "as is" (e.g., when no damage is involved). Warp Sense is very useful to planewalkers. Casters may also be particularly interested in:
- Gate Seal
- Gate Ward
- Portal Alarm
- Portal Beacon
Here's a nice 3e conversion of all the spells: http://www.enworld.org/ericnoah/conversions/planewalker/spells.html
(I have the 2e Planewalker's Handbook if we need the original source.)
Haelra's Chains
Level 2 Necromancy
Casting Time: 3 rounds
Range: Touch
Components: V,S
Duration: Concentration, up to 1 hour
You touch a creature which has two of its wrists or ankles touching (e.g., together, crossed). Its wrists or ankles may be in front of or behind its back. If the creature moves it wrists/ankles while you're casting the spell, the spell fails.
The target must succeed on a Constitution saving throw or have its wrists/ankles paralyzed and connected for the duration. The connection can be tight like glue or loose like a short chain. Every 1 minute the target can make another Constitution saving throw. On a success, the spell ends on the target.
This spell causes the actual flesh and bones of the wrists/ankles to be magically chained together. It may not work on a creature without flesh and bone (e.g., a construct). There are no permanent side effects.
At Higher Levels. When you cast this spell using a spell slot of 3rd level of higher, you can target one additional creature and/or pair of wrists/ankles for each slot level about 2nd. Each creature must be touched while you're casting the spell.