Spellcasting. The overlord is a 8-level spellcaster. Its spellcasting ability is 14 (spell save DC 5, +12 to hit with spell attacks). The overlord has following  spells prepared: 

Cantrips : fireball, acid splash
1st level (2 slots): arms of hadar, burning hands

2nd level 2 slots: cloud of daggers, cordon of arrows

3rd level 2 slots: elemental weapon, fear

4rth level 2 slots: Evards black tentacles, giant insect

5th level 4 slots: cloud kill ,flame strike ,hold monster, mislead

6th level 3 slots: disintegrate, create undead, circle of death

7th level 1 slot: finger of death

8th level 3 slots: incendiary cloud, maze, sunburst

Action Melee Attack. 

Great sword: range 50ft, 2d20 slashing

flail: range 70ft,3d20 bludgeoning

Action Ranged Attack. 

Lava blast: rang 120ft, 3d20 fire damage

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