Aerial Servant (from the people at Dungeon Master's Guild)
Medium-Size Elemental (Air)
Hit Dice: 16d8+64 (136 hp)
Initiative: +9 (+5 Dex, +4 Improved Initiative)
Speed: Fly 60 ft (perfect)
AC: 19 (+5 Dex, +4 natural)
Attacks: Slam +21/+16/+11
Damage: Slam 2d8+12
Face/Reach: 5 ft by 5 ft/5 ft
Special Attacks: Improved grab, constrict, windblast
Special Qualities: Elemental, damage reduction 10/+1, natural invisibility, find target, empathic link
Saves: Fort +9, Ref +15, Will +5
Abilities: Str 26, Dex 21, Con 18, Int 4, Wis 10, Cha 11
Skills: Intuit Direction +7, Listen +7, Move Silently +13, Search +4, Spot +7
Feats: Improved Initiative, Weapon Focus (slam)

Climate/Terrain: Any land and underground
Organization: Solitary
Challenge Rating: 1 2
Treasure: None
Alignment: Always neutral
Advancement: 1 7-33 HD (Medium-size); 34-48 HD (Large)

This creature is a form of air elemental native to the plane of Elemental Air, as well as the Ethereal and Astral planes, and can be summoned to the Material Plane by spell casters foolish enough to do so.
Normally invisible, if seen on their home plane, they resemble legless humanoids of sparkling blue smoke, with empty eyes, a slash for a mouth, and long, four-fingered hands.

Combat: They rarely engage in combat, using a shearing blast of intensely focussed wind to pummel their opponents when they do so and using their slam attack if pressed.
Improved Grab (Ex): To use this ability, the aerial servant must hit an opponent of up to Large size with its slam attack. If it gets ahold, it can constrict.
Constrict (Ex): An aerial servant deals 2d8+12 points of damage with a successful grapple check against Large or smaller creatures. Because it seizes victims by the neck, a creature in the aerial servant's grasp cannot speak or cast spells with verbal components.
Wind Blast (Su): Line 5 feet wide, 5 feet high, and 80 feet long, once every 1d4 rounds; 4d8 points of damage and creatures of Large or smaller size are knocked down and back 1d4x10 feet. A successful Reflex save (DC 26) halves the damage and negates the knockdown.
Natural Invisibility (Su): This ability is constant, allowing the aerial servant to remain invisible even when attacking. This ability is inherent and is not subject to the invisibility purge spell.
Find Target (Sp): When ordered to locate a creature or an object, an aerial servant does so unerringly, as though guided by discern location. The caster must know the designated creature.
Empathic Link (Ex): When summoned, the aerial servant creates a mental link between itself and the caster who summoned it. Should the aerial servant fail the mission it has been assigned, it will return to the aerial servant fail the mission it has been assigned, it will return to the caster and attack. The aerial servant can find the caster as long as they are on the same plane of existence. Should the caster leave the plane, it will temporarily break the link, though it will be reestablished once the caster returns to the same plane as the aerial servant.
Elemental: Immune to poison, sleep, paralysis, and stunning. Not subject to critical hits. Aerial servants have darkvision with a range of 60 feet.

Summoning an Aerial Servant
An aerial servant is summoned using the clerical spell planar ally or the arcane spell planar binding.
An aerial servant obeys the commands of the one who conjured it with respect to finding and returning whatever object or creature is described. Of course, the object or creature must be such as to allow the aerial servant to physically bring it to its caster. It will also disappear when its duty is fulfilled, it is dispelled, the caster releases it, or the caster is slain.
If an aerial servant is prevented from completing its mission, it will return to the caster and either attack or attempt to carry him back to the elemental plane of Air. The unfortunate spell caster will likely never be seen again.
The Aerial Servant first appeared in the 1e MM (Gary Gygax, 1977).

Algoid (from the people at Dungeon Master's Guild)
Medium-Size Plant
Hit Dice: 5d8+15 (37 hp)
Initiative: +0
Speed: 20 ft
AC: 15 (+5 natural)
Attacks: 2 slams +7 melee
Damage: Slam 1d8+6
Face/Reach: 5 ft by 5 ft/5 ft
Special Attacks: Animate trees, stun
Special Qualities: Plant, damage reduction 20/+2, weapon immunities, fire immunity, susceptibilities, low-light vision
Saves: Fort +7, Ref +1, Will +1
Abilities: Str 19, Dex 10, Con 16, Int 4, Wis 10, Cha 11
Skills: Hide +4*, Listen +4, Move Silently +4

Climate/Terrain: Temperate and warm forest, marsh, and underground
Organization: Solitary, pair, or cluster (3-6)
Challenge Rating: 4
Treasure: 50% coins; 50% goods; 50% items
Alignment: Always neutral
Advancement: 6-9 HD (Medium-size); 10-15 HD (Large)

The algoid is a living colony of algae that has developed some semblance of intelligence and mobility. The algoid appears as a 7-foot tall, green humanoid with coarse, rough features.

Combat:
Animate Trees (Ex): 90-foot range, two trees, as the liveoak spell cast by a 10th-level druid.
Stun (Ex): If an algoid delivers a successful critical hit to an opponent, the opponent must succeed at a Fortitude save (DC 16) or be stunned for 1d4 rounds.
Plant: The algoid is immune to poison, sleep, paralysis, stunning, and polymorphing. It is not subject to critical hits and is immune to mind influencing attacks.
Weapon Immunities (Ex): Algoids take one-half damage from slashing or piercing weapons.
Immunities (Ex): Algoids take no damage from fire or electricity.
Susceptibilities: Control water deals 1d6 points of damage per caster level to an algoid.
Skills: The algoid receives a +4 racial bonus to Hide*, Listen, and Move Silently checks.
*They receive a +12 racial bonus to Hide checks when in a swampy or forested area.
The Algoid first appeared in the 1e FF (1981).