Drakes

Bloodseeker Drake, Crested Felldrake, Guard Drake

For some reason, adventure authors love adding spiders and small drakes as critters and pets to round out encounters. With few low-level options, who can blame the authors? Nobody wants to fight lovable beasts like wolves.

Spiders

Deathjump Spider, Spider of Lolth

Elementals

Medium Earth Elemental, Loyal Earth Elemental, Medium Fire Elemental

Medium sized elementals appear frequently in adventures of all levels. Earth elementals nose ahead of fire as the most common. You can skip the water elemental figures.

Sadly, Wizards never produced a translucent, medium-sized air elemental. The dirty Shardstorm Vortex stands as the best alternative. The solid-plastic air elemental in Harbinger may rank as the worst figure ever to appear in a D&D miniature set.

Thugs

Human Thug

Thugs, especially armed with clubs, appear frequently in heroic-tier adventures.

Guards with pole arms

Human Town Guard, Royal Guard, Phalanx Soldier

For some reason, town and palace guards always carry spears or halberds.

Bowmen

Free League Ranger, Graycloak Ranger, Militia Archer

Most encounters call for an enemy capable of ranged attacks. In urban encounters, bowmen appear all the time.

Overall, too few humanoid miniatures sport ranged weapons.

Elf Warmage

Elf Warmage

I always carry a few miniatures suitable for player characters that I can loan out. Players borrow this elf warmage more than any other figure. Plus, she often finds work as a patron, bystander, or fey villain.

Statues

Animated Statue, Earth Element Gargoyle

I love to toy with players’ metagame expectations. Every D&D player knows that statues invariable come to life and attack─at least when they have a miniature on the map. So whenever a statue appears on a map, I drop a statue or gargoyle figure on top of it. Inevitably, the players edge nervously around the potential hazard. It never ceases to amuse me. Does that make me a mean DM?

Of course, sometimes, the statues really do attack.

Skeletons and zombies

Boneshard Skeleton, Skeleton, Warrior Skeleton, Zombie, Zombie

In the early days of the hobby, dungeon designers could put living creatures in a remote and unexplored dungeon without a source of food, and no one would care. Now days, that sort of design will get your DM card suspended. This surrender to logic makes undead more useful than ever.  (This also holds true for the elementals, above.) In my opinion, the unarmored, boneshard skeleton ranks as the best. The need for ranged undead means blazing skeletons and skeletal archers also see tons of use

Spirits

Lurking Wraith

I think the Lurking Wraith ranks as the single best D&D miniature figure ever produced. Not only does the translucent figure look great, but it works in numerous encounters at every level. Unfortunately, I’m not the only one who loves this figure. Miniature vendors charge about $9 each, much more than the typical price of a medium-sized, uncommon figure. You can get unpainted, blue versions in the Castle Ravenloft board game. I hope a painted version reappears in the upcoming, undead-themed, Dungeon Command set.

Goblins

Goblin Sharpshooter, Goblin Cutter, Goblin Skullcleaver

The ubiquitous opponent for beginning characters. Many different goblins appeared in the D&D miniatures run, but the best came in the last few sets. Get a bunch with melee weapons and bunch with ranged weapons. They’re cheap.