Battle Royale Arena

Infamous Battle Royale Arena designed to settle combat between individuals or teams. The arena also participates in the combat as well, with both offensive and defensive spells cast at the end of the initiative order (the Arena must always be last in the initiative order). 

Arena can take on the terrain or map of the DMs choosing.

Arena is meant for high level PCs and NPCs.

Arena cannot be attacked or damaged by PCs or NPCs. All attacks by the Arena are random, and is resolved by rolling the appropriate die for offensive (1d20) and defensive spells(1d10), roll a die for targeting the PC(s) for spell effects (1d number of PCs), or by a random location determined by the DM (for 4 quadrants of a map use a 1d4).

Battle Royale Arena: The Arena alternates between offensive and defensive spells. For example, the arena will randomly target an area of the map with a fireball, on the next turn the arena can cast cure wounds on a random PC. Roll 1d20 for offensive spells, and 1d10 for defensive spells 

Spellcasting. The Arena is an 20th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 21, +12 to hit with spell attacks).

Offensive Spells 1d20

1. Maddening Darkness Targets all creatures

2. fireball Targets random location

3 to 6. Lightning Bolt Targets random creature(s)

7 to 11. Magic Missile Targets all creatures

11 to 14. Slow Targets all creatures

15. Wall of Fire Random location

16 Wall of Ice Random location

17. Cone of Cold Targets all creatures (no range restrictions)

18. Prismatic Spray Targets all creatures (no range restrictions)

19. Sunburst Targets one random location

20. Meteor Swarm Targets 4 random locations

Defensive Spells 1d10

1. Haste Targets one random creature

2. Otiluke's Resilient Sphere Targets one random creature

3. Beacon of Hope Targets two random creatures

4. Cure Wounds cast at 5th Level, Targets two random creatures

5. Cure Wounds cast at 5th Level, Targets two random creatures

6. Cure Wounds cast at 5th Level, Targets two random creatures

7. Mass Cure Wounds Targets all creatures

8. Death Ward Targets one creature

9. Aid Targets all creatures

10. Resurrection Can only target a Knocked out creature.

Arena has no bonus actions.

Reaction Name. Arena has no reactions.

Arena has no Legendary Actions.

Arena is not Mythic.