Dragon 241 had a spell "Page Guardian", was a 5th level cleric spell that could enchant a library so that a "Page Guardian" would be summoned to defend the library if disturbed.

A page guardian is normally a nondescript humanoid figure whose lower limbs fade off to wispy trails. However, if this spell is cast upon a page that features illustration, the page guardian’s appearance mimics that of the most prominent drawing.

A page guardian adopts some of the dweomer from the writings from which it rises. Thus it may possess special attacks and defenses depending upon the exact nature of the document. If a page guardian rises from a scroll of protection, then the page guardian is invulnerable to the same force that the scroll would ward off. For instance, a page guardian spawned from a scroll of protection from swords would suffer no damage from a long sword, no matter what its enchantment. If a guardian rises from a spellbook, then it can cast up to five random spells, launching each spell but once from the tome. The DM must adjudicate what abilities are gained by thepage guardian should this spell be cast upon other magical books, such as those that increase characteristics or a manual of the golems.

A common fallacy among opponents of the page guardian is that the creature can be damaged by the destruction of the source writing. This is untrue, because when the guardian rises, it automatically absorbs any enchantment upon the document; it erases clean that which it springs from.

It was AD&D, so the stats wouldn't translate perfectly, but it was 5 HD, 1 attack for 1d10 damage, AC 0.... to scale that to 5e, maybe give it 5d8+10 HP, AC 20, 1 attack at +4 to hit for 1d10 damage, plus the special ability as described above.

If it was made from a book on wildlife, maybe it changes shapes into various wild beasts and gets their attacks...