Azog, Moria's Ruin

Azog can destroy Gollum to draw a card and amass Goblins 2, after which Gollum can be returned to hand and replayed for another drain trigger.

Chapter I can discard Azog and create a Human Soldier token, then chapter II returns Azog and lets its enters ability destroy that expendable token to amass Goblins and draw a card.

Gone Fishing can blink Azog to reuse its enters ability, while also blinking another permanent for value; the returned Azog can convert another expendable creature into an Army and a card or remove an opposing creature.

Using Azog on your own nontoken creature triggers Part in Friendship, so the creature is converted into an Army and a card while the enchantment supplies another creature from your library.

Azog can destroy the Pair on entry, drawing a card because you controlled it. The Pair's death trigger amasses 4, while Azog also amasses 1 from its power, producing five Army counters in total.

Azog can destroy Front Porch Sentries, causing you to draw a card and amass Goblins 2 from Azog while the Sentries' death trigger gives an opposing creature -1/-1.

After Gundabad Opportunist provides its exiled card, Azog can destroy it to draw a card and amass Goblins 4. This converts the fragile 4/2 body into a large Army while retaining the Opportunist's enters-the-battlefield value.

After Stony-Voiced Goblins has forced a discard, Azog can destroy the spent 1/1 to draw a card and amass Goblins 1, extracting multiple pieces of value from the same cheap creature.

Azog can destroy your Rampager after it has grown: Azog amasses equal to Rampager's power and draws a card, while Rampager's own death trigger amasses that much again. This effectively doubles its power as Army counters while replacing the card.

After Azog destroys an opposing creature, Supper for Spiders can immediately return that card under your control as a Food artifact, substantially offsetting the Army Azog gives its former controller.

When Azog amasses your own Army, the counters trigger The Great Goblin for 2 damage — removal that also burns.

Azog can destroy an expendable creature to amass based on its power and draw a card, creating or enlarging a counter-bearing Army that Great Ugly-Looking Goblin then grants menace.

Repeatedly blinking Azog lets each chapter convert another expendable creature into an appropriately sized Goblin Army and a card; this is especially effective when recycling an Army whose power comes from counters.

Desolation Prowler can raise its power to 4 before Azog destroys it, letting Azog replace the two-drop with a 4/4 Goblin Army while also drawing a card.

When Azog targets an opposing creature, Head of the Hunt replaces that creature's death with exile and creates a 2/2 Wolf for you; Azog still makes that opponent amass based on the targeted creature's power.

Elrond's activated ability can blink Azog for another enters trigger, allowing Azog to repeat its removal or creature-to-Army conversion while Elrond also blinks a second permanent.

Chapter II supplies an Army that Azog can destroy under your control, drawing a card and then amassing equal to its power; this effectively rebuilds the Army while converting the original into card advantage.

Returning Azog from your graveyard to your hand triggers Along the Crooked Way to amass Goblins 1, and recasting Azog then provides another enters trigger that can convert a creature into additional Army counters and a card.

Azog reliably causes a creature to die with its enters ability, reducing Dreaded Bat-Cloud to just {1}{B} and letting you add a 4/2 flying deathtouch threat in the same turn.

Equipping an expendable creature with Ragged Short Spear increases the power Azog converts into Goblin Army counters by two; the Equipment survives the creature's destruction and can later be moved onto the Army.

Azog's enters ability guarantees a death when it has a legal target, triggering Great Fierce Bee to scry whether Azog destroys an opposing creature or converts one of your own creatures into an Army and a card.