Blue Eyes Tiny Dragon

B.E.T.D  In combat, the Betty shares your initiative count, but it takes its turn immediately after yours. It can move and use its reaction on its own, but the only action it takes on its turn is the Dodge action, unless you take a bonus action on your turn to command it to take one of the actions in its stat block or the Dash, Disengage, Help, Hide, or Search action.

If the mending spell is cast on it, it regains 2d6 hit points. If it has died within the last hour, you can use your smith’s tools as an action to revive it, provided you are within 5 feet of it and you expend a spell slot of 1st level or higher. The steel defender returns to life after 1 minute with all its hit points restored.

Lightning Breath (Recharge 5–6). The dragon exhales lightning in a 30-­foot line that is 5 feet wide. Each creature in that line must make a DC 12 Dexterity saving throw, taking 22 (4d10) lightning damage on a failed save, or half as much damage on a successful one.

Self Destruct: Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw of 14. A target takes (8d6) fire damage on a failed save, or half as much damage on a successful one. Upon use of this feature the Betty is destroyed. Source: Red wyrmling 

Haste: The dragon lands on a chosen creature and casts haste. Cannot leave target or take another action or else the effect ends. Can only be used once a day unless recharged with a level 3 spell slot     

Choose a willing creature that you can see within range. Until the spell ends, the target's speed is doubled, it gains a +2 bonus to AC, it has advantage on Dexterity saving throws, and it gains an additional action on each of its turns. That action can be used only to take the Attack (one weapon attack only), Dash, Disengage, Hide, or Use an Object action. When the spell ends, the target can't move or take actions until after its next turn, as a wave of lethargy sweeps over it.  Source: adult blue dragon

Nibble: Melee Weapon Attack: +2 to hit, reach 5 ft., one target. Hit:  (1 + 3) Piercing damage.