Iron Harvest asks you to fight a dieselpunk war with two currencies. Iron builds everything, but oil is what separates a mech from a rifleman, and KING Art Games has rewritten the mech price list repeatedly since launch. That makes a cost-effectiveness question unavoidable: given the oil you have, which walker actually wins the fight in front of you? This guide ranks the launch trio — Polania, Rusviet and Saxony — by value against role, then sets out the hard and soft counters that decide those matchups.
What this covers: Every Polania, Rusviet and Saxony mech ranked by cost-effectiveness against its role, plus the counter matrix that decides factionfaction. An in-game group or nation players can align with or fight against, with its own goals and reputation system. matchups. Why it matters: KING Art’s cost rebalances changed which mech is worth its oil, so a cheap answer to your opponent’s composition now beats an expensive unit with nothing to shoot. Who should pick this: Skirmish and ranked players choosing mechs for a matchup, and anyone learning to read Iron Harvest’s dieselpunk economy. (Usonia, added with the Operation Eagle expansion, is outside the launch trio and is not ranked here.)
The dieselpunk economy: iron, oil, and the tier-2 gate
Mechs are built at the workshop, and the specialised units need the Advanced Workshop — the Polania Wiki lists the Łowca, Tur, Erlkönig and Serp as advanced-workshop production, while generalists like the Śmiały, Grimbart and Isegrim can come from the basic workshop. Iron is the bulk cost; oil is the mech tax.
The two defining balance passes both attacked the infantry-to-mech transition. In Change Log #20 KING Art wrote that light, tier-1 mechs were “often skipped out on and also buried under a flood of infantry,” and responded by cutting workshop costs — Polania from 400 to 250 iron, Saxony from 450 to 250, Rusviet from 500 to 300 — while raising Advanced Barracks upgrade costs. The December 2021 Changelog 25 pushed further, stating that “Mech and exoskeleton build costs have been adjusted to lower the barrier of building tier 2 mechs,” and added that tier-2 mechs were made “clearly stronger than the tier 1 mechs.”
The practical lesson is that oil, not iron, gates how many mechs you can sustain. A 50-oil Straznik or Grimbart trades readily; a 180-oil Tur or 190-oil Kaiser is a commitment you make once. Cost-effectiveness is therefore a function of role: the cheapest unit that answers the enemy’s composition is the correct purchase, even if a superheavy would win a hypothetical duel.
Armor classes and the rear arc
Four armor classes decide every damage exchange in the game. The Fandom wiki’s Armor page defines them:
- Unarmored — all infantry. Light weapons and grenades chew through it.
- Light — “small and fast mechs like the PZM-9 ‘Straznik’ or the PZM-7 ‘Smialy’, as well as for exosuits.” It can be damaged by small arms but is “very vulnerable to field cannons, gunners and mechs with anti-mech weapons.”
- Medium — “the armor class for the most mechs.” Only slightly damaged by light weapons, but vulnerable to field cannons and anti-mech mechs.
- Heavy — “the heaviest mechs,” such as the Żółw. Only field cannons and anti-mech mechs “can inflict meaningful damage.”
The same page adds the detail that decides flanks: many mechs have rear weak points where “the damage is doubled.” A mech-hunter that gets behind a heavy is doing double work, which is why the Śmiały and Serp are played as flankers rather than line-fillers.
The launch roster at a glance
Costs are the current values from Changelog 25 unless noted; HP and armor are from the unit pages. Tiers in the next section are this guide’s judgement, not a sourced ranking.
| Mech | Faction | Role | Armor | HP | Iron | Oil | Pop |
|---|---|---|---|---|---|---|---|
| PZM-9 Strażnik | Polania | Anti-infantry MG | Light | 600 | 280 | 50 | — |
| PZM-7 Śmiały | Polania | Scout / raider | Light | 850 | 350 | 90 | 4 |
| PZM-13 Mocny | Polania | Siegesiege. A timed, large-scale attack on a settlement — attackers try to destroy it, defenders try to hold it. tank | Medium | — | 400 | 110 | — |
| PZM-11 Łowca | Polania | Mech hunter | Medium | 1200 | 550 | 80 | 5 |
| PZM-16 Żółw | Polania | Troop transport | Heavy | 800 | — | 120 | — |
| PZM-24 Tur | Polania | Super-heavy line | Heavy | 1700 | 720 | 180 | 7 |
| Sd. KS 49 Grimbart | Saxony | Anti-infantry gatling | Light | 1100 | 300 | 50 | 4 |
| Sd. KS 78 Isegrim | Saxony | Generalist tank | Medium | 950 | 400 | 80 | 4 |
| SLL 33 Erlkönig | Saxony | Artillery | Light | 750 | 300 | 110 | 5 |
| SKS 156 Wotan | Saxony | Mech hunter | Medium | 950 | 500 | 130 | — |
| SKS 300 Kaiser | Saxony | Super-heavy line | Heavy | 3000 | 750 | 190 | — |
| SHM-78 Ognivo | Rusviet | Flamer | Medium | 750 | 300 | 40 | — |
| SHM-86 Kolokol | Rusviet | Anti-infantry bomber | Light | 900 | 330 | 70 | 4 |
| SHM-69 Serp | Rusviet | Melee linebreaker | Heavy | 1400 | 500 | 80 | 6 |
(Strażnik HP 600, Śmiały 850, Grimbart 1100, Isegrim 950, Ognivo 750 and Kolokol 900 are the post-Change Log #20 values; Wotan 950 is the Changelog 25 increase; Serp 1400 is from Changelog 18.)
The tier list: cost-effectiveness by role
These placements are editorial judgement. They weigh cost against what the mech actually does in its niche, not raw power.
| Tier | Mech | Why it sits here |
|---|---|---|
| S | PZM-9 Strażnik | The cheapest mech in the launch trio at 280 iron / 50 oil, and a dedicated anti-infantry suppressor. TheGamer calls its “cheap price both as a Reserve Unit and as a normal unit” its defining virtue. |
| S | PZM-7 Śmiały | 350/90 buys the second-fastest unit in the game and a rifle that does equal damage to light and medium armor (70). En-parity value in raids and recon. |
| S | Sd. KS 78 Isegrim | Versatility at 400/80 with only 4 population; the Fandom page calls it “a highly versatile unit with few true weaknesses.” |
| S | SHM-86 Kolokol | 330/70 for Rusviet’s fastest mech, with 85 damage against light armor and 65 against medium — the cheapest hard answer to a light-mech wolfpack. |
| A | PZM-11 Łowca | Its oil cost was slashed from 150 to 80 in Changelog 25, and its Sting ability deals 465 damage to every armor class at base, 534.75 once veteran. Slow and short-ranged, but the best anti-armor value in Polania. |
| A | SKS 156 Wotan | 500/130 buys 170 damage against light armor and 130 against heavy at long range. The weakness is survivability, not output. |
| A | SHM-69 Serp | 500/80 for heavy armor, 1400 HP and a scythe that does 100 damage to all armor types. Melee range is the tax. |
| A | Sd. KS 49 Grimbart | 300/50 for the “most durable light-armored mech,” per the Fandom page, and a gatling that devastates infantry. |
| A | SHM-78 Ognivo | 300/40 is the cheapest mech oil cost in the trio, and its flamethrowers “ignore cover,” hitting infantry in buildings and behind barricades. |
| B | SLL 33 Erlkönig | 300/110 for the longest range in the game, but light armor and no defense; it needs spotters and screens to function. |
| B | PZM-24 Tur | 720/180 and 1700 HP, but its own wiki page admits it is “not ideal against other heavy mechs” and loses one-to-one to its peers. |
| B | SKS 300 Kaiser | 750/190 for 3000 HP and a 140/125 cannon — strongest in a straight fight, but the highest oil cost on the board. |
The counter matrix
Hard counters are dedicated answers; soft counters are cheaper or situational. Every armour claim traces to a unit or Armor page above.
| Threat | Hard counter | Soft counter | Why it works |
|---|---|---|---|
| Infantry swarm | Grimbart, Straznik, Ognivo, Kolokol | Machine gunners (suppression) | Anti-infantry mechs deal area or gatling damage; suppression pins squads for the follow-up. |
| Light-mech pack (Śmiały) | Isegrim, Kolokol, Grimbart | Field cannons, gunners | Light armor is “very vulnerable to field cannons, gunners and mechs with anti-mech weapons.” |
| Medium line (Isegrim) | Łowca, Wotan | Field cannons | Anti-mech cannons out-penetrate medium armor; Śmiały’s rifle also matches 70 damage here. |
| Mech hunter (Łowca/Wotan) | Artillery, Śmiały flank | Serp rush | Both hunters are slow or fragile; artillery outranges them and the Śmiały outruns them. |
| Heavy mech (Serp, Żółw) | Artillery, field cannons | Łowca, Wotan | Heavy armor resists small arms but not dedicated anti-armor fire. |
| Super-heavy (Tur, Kaiser) | Artillery + anti-mech focus | Flank with fast mechs | The Tur page flags field cannons and artillery as its answer, and its slow turn leaves the rear weak point open. |
| Artillery (Erlkönig, Nakovalnya) | Śmiały, Serp flank, Wotan | Any fast raider | Artillery is light-armored, immobile when deployed, and has a minimum range dead zone. |
Reading each faction
Polania is the cheap-and-fast roster. The Strażnik and Śmiały do the early work for 280 and 350 iron, and the Łowca’s reduced oil cost makes the anti-armor transition cheaper than it used to be. Polania’s weakness is durability: Gamer Journalist’s faction tier list notes that “most of Polania’s mechs aren’t cut out for prolonged combat without an engineer on standby” — so trade the cheap units, do not park them.
Saxony pays more and gets more. The Isegrim is the value pick, but the Wotan and Kaiser are expensive oil commitments — Gamer Journalist’s Saxony guide describes the faction as wanting a slow start that snowballs into a mech army, which only works if those expensive units survive to fight, so screen the Wotan and never lead with the Kaiser.
Rusviet trades range for bulk. The Kolokol and Ognivo are cheap anti-infantry and anti-structure tools, and the Serp is a heavy mech priced at 80 oil — but the whole faction leans close-range, which is exactly why Gamer Journalist’s tier list ranks its short-range roster as the most exploitable. Buy Kolokols to cover the approach, then commit the Serp to the flank.
Next read
- For how the patch history reshaped each faction, see Iron Harvest Meta Shift: Cheaper Workshops, Light Mechs.
- For a comparison-driven look at another asymmetric RTSRTS. Real-Time Strategy — a strategy game where everyone plays at the same time, continuously, instead of taking turns. roster, see Tempest Rising: GDF vs Dynasty Faction Comparison.
- For a shorter RTS where a fixed unit deck replaces a mech tech tree, see Tooth and Tail Primer: Factions, the Six-Unit Deck, and Map Control in a 12-Minute RTS.