Beacon of Power

This glittering crystal known as a nether star forms within the body of the Wither. It is rare and extremely valuable, but more important is its use in creating the beacon of power. The nether star must be placed inside a container of glass and obsidian, and then put on top of a pyramid of precious stones and metals. An 8-hour ritual of attunement must then be performed, after which the beacon sends up a beam of white light into the sky.   For as long as the beacon's light has an unobstructed path into the sky, the beacon grants its effects to all those who were present and participated in the ritual, for as long as they remain within 150 feet of the beacon. The effects added by the beacon depend on the size and cost of the pyramid structure. The pyramid can be built at any size by paying the full cost for that size, or can be upgraded over time.   A large-sized pyramid costing 9,000 gp grants the following effects.

• You can use the dash action as a bonus action on your turn.
• Your jump distance is tripled.

A huge sized pyramid costs an additional 25,000 gp (34,000 gp total) and grants the previous two effects as well as the following.

• You receive a +1 bonus to AC and saving throws.
• Your melee weapon attacks deal an extra 1d4 force damage.

A gargantuan sized pyramid costs an additional 49,000 gp (83,000 gp total) and grants all of the previous effects as well as the following.

• You regain 5 hit points at the start of your turn as long as you have at least 1 hit point.

The full pyramid, also gargantuan sized, costs an additional 81,000 gp (164,000 gp total). It grants all of the above effects and the following.

• You can take an additional action on each turn.

  (credit https://www.dandwiki.com/wiki/The_Wither_(5e_Creature))