Can you polymorph into a Wyvern?

Polymorph can turn someone into a beast only.

What can you transform into with polymorph?

10 Best Things To Polymorph Into (D&D 5E)

Giant Ape. Source: Monster Manual.
Giant Owl. Source: Monster Manual.
Tyrannosaurus Rex. Source: Monster Manual.
Bat. Source: Player’s Handbook.
Flying Snake. Source: Monster Manual.
Giant Shark. Source: Monster Manual.
Giant Elk. Source: Monster Manual.
Giant Octopus. Source: Monster Manual.

Can you transform into a dragon in DND?

For 1 minute or 1 hour once per long rest, he can transform to a dragon of a specific power level. The higher in level he gets, the stronger of a dragon he can turn in to. The specifics of this would be up to you to decide what you’re willing to allow.

Can you turn yourself into a dragon in polymorph?

You can use Polymorph on yourself, as you are a creature you can see within range. But you cannot turn yourself into a dragon, as you can only turn into Beasts using the spell. The new form can be any beast whose challenge rating is equal to or less than the target’s (or the target’s level, if it doesn’t have a challenge rating).

Can a druid turn a character into a dragon?

Druids have an ability somewhat similar to polymorph called Wild Shape. However, like polymorph, it can only be used to transform into beasts. There are other differences between the spell and the druid feature as well, but those are unimportant for this question as long as you understand they are separate things.

Can a 9th level polymorph turn a creature into a creature?

The 9th level spell, True Polymorph, has no such restriction. Creature into Creature. If you turn a creature into another kind of creature, the new form can be any kind you choose whose challenge rating is equal to or less than the target’s (or its level, if the target doesn’t have a challenge rating).

What happens when you use polymorph on your character?

The target’s game statistics, including mental ability scores, are replaced by the statistics of the chosen beast. It retains its alignment and personality. You keep your personality but lose your mental statistics when you do this though, so you need to be cautious.