Prehistoric Circle (5e Subclass)
From D&D Wiki
You are a druid who has studied the ways of the ancient dinosaurs. You have discovered pockets of their existence and have managed to become one with them, bonding with either a deinonychus, a velociraptor, an allosaurus, a dimetrodon or an ankylosaurus.
Prehistoric Wild Shape
When you choose this circle at 2nd level, you gain the ability to use Wild Shape on your turn as a bonus action, rather than as an action. Additionally, while you are transformed by Wild Shape, you can use a bonus action to expend one spell slot to regain 1d8 hit points per level of the spell slot expended.
The rites of your circle grant you the ability to transform into more dangerous dinosaur forms. Starting at 2nd level, you can use your Wild Shape to transform into a dinosaur with a challenge rating as high as 1 (you ignore the Max. CR column of the Beast Shapes table). Starting at 4th level, you can transform into a beast with a challenge rating as high as your druid level divided by 2, rounded down.
At 2nd level, you form a bond with one of the mentioned dinosaurs. Your dinosaurs get a 1d8+Constitution modifier (or +2 whichever is higher) each level. Your companion that accompanies you on your adventures is trained to fight alongside you. Add your proficiency bonus to the beast’s AC, attack rolls, and damage rolls, as well as to any saving throws and skills it is proficient in. The beast obeys your commands as best as it can. It takes its turn on your initiative, though it doesn’t take an action unless you command it to. On your turn, you can verbally command the beast where to move (no action required by you). You can use your action to verbally command it to take the Attack, Dash, Disengage, Dodge, or Help action.
At 5th level, you and your companion gain an extra attack.
Prehistoric twin Shape
At 10th level, you gain the ability to transform into a twin of your companion. Use your companion stats and abilities in this form. Additionally, you can communicate completely with your companion in this form.
At 16th level, you can expend two uses of Wild Shape at the same time to transform into a prehistoric creature with a Challenge Rating of 15 or lower. When activating this feature you must roll 1d20 and add your Wisdom modifier to determine the number of hours you can maintain this form until you must power down.