Encounter 6 - lvl 5 to 10

1x Amethyst Dragon Wyrmling Medium dragon (gem) , typically neutral
Armor Class 17 (Natural Armor) Hit Points (10d8 + 30) Speed 30 ft., fly 60 ft. (hover), swim 30 ft.
STR 19 (+4) DEX 10 (+0) CON 17 (+3) INT 16 (+3) WIS 13 (+1) CHA 17 (+3)
Saving Throws DEX +2, CON +5, WIS +3, CHA +5 Skills Arcana +7, Perception +5, Persuasion +5, Stealth +2 Damage Resistances Force, Psychic Condition Immunities Frightened, Prone Senses Blindsight 10 ft., Darkvision 120 ft., Passive Perception 15 Languages Draconic, Telepathy 120 ft. Challenge 4 (1,100 XP) Proficiency Bonus +2
Amphibious. The dragon can breathe both air and water.
Actions Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: (1d10+4) piercing damage plus (1d8) force damage.
Singularity Breath (Recharge 5–6). The dragon creates a shining bead of gravitational force in its mouth, then releases the energy in a 15-foot cone. Each creature in that area must make a DC 13 Strength saving throw. On a failed save, the creature takes (5d8) force damage, and its speed becomes 0 until the start of the dragon’s next turn. On a successful save, the creature takes half as much damage, and its speed isn’t reduced.
Spellcasting (Psionics). The dragon casts one of the following spells, requiring no spell components and using Intelligence as the spellcasting ability (spell save DC 13):
1/day each: protection from evil and good, Tenser's floating disk, unseen servant
2x Crystal Dragon Wyrmling Medium dragon (gem) , typically chaotic neutral
Armor Class 14 (Natural Armor) Hit Points (5d8 + 10) Speed 30 ft., burrow 15 ft., climb 30 ft., fly 60 ft.
STR 14 (+2) DEX 12 (+1) CON 14 (+2) INT 14 (+2) WIS 13 (+1) CHA 15 (+2)
Saving Throws DEX +3, CON +4, WIS +3, CHA +4 Skills Perception +5, Stealth +5, Survival +3 Damage Resistances Cold, Radiant Senses Blindsight 10 ft., Darkvision 60 ft., Passive Perception 15 Languages Draconic, Telepathy 120 ft. Challenge 2 (450 XP) Proficiency Bonus +2
Actions Bite. Melee Weapon Attack: +4 to hit, reach 10 ft., one target. Hit: (1d10 + 2) piercing damage plus (1d4) radiant damage.
Scintillating Breath (Recharge 5–6). The dragon exhales a burst of brilliant radiance in a 15-foot cone. Each creature in that area must make a DC 12 Constitution saving throw, taking (4d8) radiant damage on a failed save, or half as much damage on a successful one. The dragon then gains 5 temporary hit points by absorbing a portion of the radiant energy.
Spellcasting (Psionics). The dragon casts one of the following spells, requiring no spell components and using Intelligence as the spellcasting ability:
At will: dancing lights, guidance