All warfare is asymmetric.

There are several Unit Types in Dota. A single unit can have multiple unit types at once. Nothing can alter the unit types a unit possesses.

Hero

All heroes in Dota are hero units. Heroes can gain experience, earn gold, and level up their abilities.

Creep

Creeps are basic units in Dota 2. Every unit which is not a Hero, Building, Ward or Courier is considered a creep. Creeps can belong to either faction, be neutral, or be player-controlled units. Unlike heroes, creeps do not gain experience and cannot level up. All of their stats are set values (though can still be altered by modifiers). Most creeps grant a set gold and experience bounty to heroes when killed.

List of Creep units:

Lane Creeps
Neutral Creeps, including Roshan and Tormentor
Ward

Ancient

Ancient Creeps are resistant to specific spells. They are treated as a hero unit or a creep unit depending on the spell. For example, hero units are always affected by spells as a hero, creep units are always affected by spells as a creep, but ancient units can receive either effect or none at all. What determines which effect can be used is unique to each spell.

List of Neutral units with the Ancient unit type:

Ancient Creeps, including Roshan and Tormentor
Courier

Summoned

Regural Summons

Regual summons are comparable to lane and neutral creeps when it comes to their power. A single one of them is usually not a threat, however, they can get quite dangerous when encountered in groups. Summons usually have certain abilities, giving each of them a different role. They can either be passive and used for scouting, or aggressive used in fights. Losing regular summons is usually not a big deal, since they provide rather low bounties, they expire and they can be resummoned after a short while.

A regular summon is treated like lane and neutral creeps by almost every ability. Certain abilities have specific or conditional effects against summoned units.

Regular Summon Sources

Beastmaster – Call of the Wild Hawk
Beastmaster – Call of the Wild Boar
Broodmother – Spawn Spiderlings
Enigma – Malefice^2b
Enigma – Demonic Summoning
Invoker – Forge Spirit
Lycan – Summon Wolves
Lycan – Summon Lane Wolves^2b
Nature's Prophet – Nature's Call
Undying – Tombstone
Undying – Flesh Golem^2b
Wraith King – Bone Guard
Mud Golem – Shard Split
Dark Troll Summoner – Raise Dead
Book of the Dead – Greater Demonic Summoning
Underlord – Fiend's Gate³

¹ Requires

talent.

^2a Requires

Aghanim's Scepter.

^2b Requires

Aghanim's Shard.

³ Requires selecting the corresponding facet.

Creep Hero

These summons are special in a way that they are treated as heroes by most (but not all) abilities and effects. They are more powerful than other summons and usually the "main weapon" of the heroes that summon them. Compared to most other summons, they do not come in masses but are rather strong individual units. However, as a downside, their bounty is usually quite high, their source ability has a high cooldown or they have other negative effects on the owner upon losing them, so it is important for the player to keep them alive as long as possible.

Creep-Heroes Summon Sources

¹ Requires

talent.

^2a Requires

Aghanim's Scepter.

^2b Requires

Aghanim's Shard.

Ward

For the custom Observer/Sentry Wards skins, see Custom Wards.

These summons are usually, but not necessarily, immobile and usually are immune to almost every ability (e.g. Meat Hook just flies through them). Their purpose differs heavily, depending on their abilities and capabilities. Some wards can attack, which makes them usually used offensively, while others have an aura for rather defensive uses.