Gargoyle (Doom Eternal)

The gargoyle (called the "harpy demon" or "flying demon" by fans before the Google Stadia footage was released on March 19, 2019) is a new monster introduced in Doom Eternal. Little of it was seen in the gameplay footage, but what is known is that it can flutter in the air and then land for terrestrial combat. They appear as small, frail humanoids with bat-like wings.

Google Stadia footage
In the Google Stadia game play footage, it can be seen shooting yellow fireballs at the player, and, after killing it, a codex entry message will be displayed with the confirmed name "Gargoyle".

Trivia
A flying demon called the "imp" was originally detailed in the Doom Bible by Tom Hall during Doom's initial development, before the name of imp was reassigned to what was then known as the "demon trooper." It is presently unconfirmed whether or not this detail has had an influence on this new monster design.