I’d put my six-pounder anti-tank guns in the perfect position to halt the Tigers’ advance. The German tanks would have to cross the bridge, keeping them packed together, and the derailed train on their flank would keep them from spreading out too much before they came into range of my British gunners’ heavy ordnance.

Being the twelfth and last wave of this game of Company of Heroes 3: Final Stand, if I could put down the tanks' advance I'd win the match and take home a healthy bushel of perk points to upgrade my faction for future matches.

But then the blasted Luftwaffe arrived.

I didn't notice the strafing markers that appeared on my minimap. I was too busy micromanaging the movements of my Canadian shock troops, infantry section, and snipers – the fleshy soldiers can face heavy armour, but only when they're protected by heavy cover. The off-map Messerschmitts made their first pass and picked off several of my gun crew.

The Wehrmacht forces were beginning their advance from their lines to the north and here I was relocating my anti-tank guns to get them out of the path of the next strafing run. My defensive line was all out of sorts when the Tiger tanks arrived, and they rolled straight through my defenses.

In Final Stand, the only thing that matters is keeping your HQ alive. With that destroyed it's game over. Without my anti-tank guns, I had to rely on my infantry, all of whom were hiding behind sandbags as the Tigers passed. Now they would have to chase the heavy armour down before the Germans reached my base.

I did still have an ace in the hole: a Crusader III Medium Tank freshly built back at HQ. My British armour may not be a true rival for the German machinery but it'd surely give Jerry a jolly run for his m… Nope, the wave of Tigers exploded the Crusader in just a few shots.

By the time my infantry caught up with the tank wave the game was already lost – they could barely dent the thick armour as the Tigers blasted my HQ to shreds. In hindsight, I should perhaps have selected a lower difficulty level for my first game of Final Stand.

Company of Heroes: Final Stand is a standalone spin-off of Relic's World War 2 RTS series. Gone is the finely constructed campaign and in its place is a roguelite horde mode. Each game sees you picking one of the game's four factions – British, Americans, Wehrmacht, or Afrikakorps – and trying to survive twelve rounds against a strengthening enemy.

At the start of each game you're in a weak state. You have a tiny roster of units you can field – in the case of the British, just engineers and a slow-moving anti-tank gun – and your enemy will soon outnumber and outgun you. Happily, with each wave your capabilities expand. You might be offered two new unit types to pick from, or two passive upgrades, or two active abilities. This means from game to game, the forces you can field and how they behave changes depending on what cards you draw.

In one game I picked the 30cwt LRDG Truck in an early wave, giving me a fast moving truck with a heavy machine gun that was exceptionally good at cutting down enemy troops advancing on foot. In another, I only picked infantry units for the first eight waves or so, giving me a battlegroup that, while requiring regular reinforcement, was very difficult to wipe out because any time my units were thinned down to a single soldier, I'd hit the retreat button and send them back to HQ to get back up to full strength.

The passive upgrades can also make big changes to how your units perform on the battlefield. Buffing your vehicles armour, or the bonuses cover provides your infantry, or how quickly your engineers can repair vehicles and buildings. Active abilities, meanwhile, can turn a battle. Calling in a well-timed artillery strike or bombing run can break the momentum of an enemy advance. Depending on what units you've picked, selecting complimentary perks and abilities can make them much stronger in battle.

From wave to wave, you need to adapt your forces to different threats. You might face an assault from flamethrower-armed engineers in one wave and a push from mortar troops and tanks in the next. Sometimes it can feel like the waves you're facing are hand-picked to dissect your forces, but I'm assured by lead designer Ross Cockburn that "They're not specifically countering you." Though, he does make me doubt his honesty immediately when he adds "But it's not fully random either." Cockburn explains that "[The AI's] trying to pick trends and stick to certain unit types throughout a run. So in one run, it might decide at the start that it's going to prefer one unit type over another."

Cockburn, who previously worked on Age of Empires 4's roguelike mode, The Crucible, said that when an enemy wage is completely random "it's hard to learn from what the AI is doing and build a roster and a strategy that is going to work for you." So, in Final Stand, what you're facing is "very layered under the hood, how it's actually deciding what kinds of waves to throw at you."

Where the enemy does embrace chaos are the dynamic events it throws at you. These are things like the strafing runs that cut through my gunners, or phosphorus airdrops that can torch entrenched infantry, or waves of exploding Goliath Demolition Vehicle. "From wave to wave, there's actually more random craziness happening with these events," game director Eric Wrobel explains. "So you can have the same event happen like five times in a row. We found it's more fun to have that random craziness going on versus with the wave system that Ross designed.

"We're not studying the player and deliberately trying to counter them with stuff like this," Cockburn adds. "We're trying to make it the other way around, where the AI is being the one that's less predictable and it's the player's job is to counter that." Like how I should have adapted to the strafing run that broke up my defensive line right before the Tiger tanks hit.

Still, even with the dynamic events it's not entirely random either. "In an earlier version we made it so every wave [The AI] would pick a new ability to throw at you," Cockburn says, "which basically meant as soon as you've started to formulate a strategy to counter one ability it would move onto the next one. There wasn't much for you to strategise with that. And so where we've moved instead is that once it picks abilities it sticks with them for a little while, letting you realise what an enemy's doing and adjust your strategy."

With the preview build of Final Stand I've been playing, I've solely been fielding the British faction. It's one part patriotism and one part time poverty. When you first start Final Stand, every faction is in its most basic state. However, as you play matches you earn perk points that can be spent to buy permanent upgrades for that faction. With four factions and entirely separate perk trees, in the interests of time, I thought it best to focus only on exploring one.

Most of the British perks are invisible number buffs – adding health to your infantry, reducing the time it takes new units to train, upping the turret swivel speed of your tanks – but there are a few that make tangible changes to the battlefield. For instance, one upgrade adds new functionality to your outposts. These defensive structures are dotted about the outskirts of your map and for every round they survive you earn additional perk points. However, when you start Final Stand, they've no way to defend themselves. There is a handy little perk, however, that fits the valuable buildings with a machine gun nest and a passive self-heal. It won't hold off the horde but it will give them a little fightback.

I'd rather see more perks like the outpost upgrades. The invisible number buffs do make the game easier, but only because on the higher difficulty levels the enemy units have been similarly buffed. Beating the top-level difficulty without any perks is basically impossible.

"We've noticed that our really top-level players were able to beat it with around 25% of the tree," Wrobel says. "But we have people that are at the top of the ladder working for us and playtesting, so that's sort of the cream of the crop. If you're not a really top-level player, you can unlock the whole [perk tree] and be able to tackle those high difficulties."

I've played about seven hours of Final Stand so far and, at 40 minutes a game, I've barely scratched what it has to offer. I've not touched the other three factions, and I'd say I've unlocked less than 10% of the Brit's perk tree. However, I'm not tempted to 100% Final Stand because even with the number of factions and the variety that its randomised rosters and dynamic abilities can bring, I suspect the formula will grow stale before I'd filled out every perk tree.

That said, I have deeply enjoyed what I've played so far. I love it when a developer picks up their game, gives it a shake, and then puts it back with all the pieces in different places. And it's worked very well in this new roguelite spin on Company of Heroes.

For two decades, the series has focused on cover and suppression, yet the old mechanics find fresh significance when every battle is about holding off and then overcoming waves of enemy soldiers. Every new assault can come from a different entry point on the map, so you are forever breaking down and moving your troops to new defensive positions, adapting your currently configured forces to the incoming threat.

Even smaller features that have been in the series since the original, like being able to pick up discarded enemy weapons find new life in Final Stand. Say you've had a game where you've not been offered a unit with a good anti-infantry weaponry. Suddenly, holding off a wave of flamethrower-armed Pioneer squad can become a godsend because now you can arm one of your units with their dropped Flammenwerfer 35.

I'm also conscious that The Final Stand I'm playing today may not be the Final Stand that exists in a year's time. "The mode is super expandable," Wrobel says. "We can drop in new bosses, we can drop in new units, we can do new tech, too, for the player as well. The systems are all set up so that we can just put these in and then it'll just randomly serve them up to you. In the future, if we want to do more stuff for this game mode, we should be able to add more stuff for players."

Still, this isn’t a review of Final Stand and I can only talk about the game in front of me and not what it may or may not do in the future. But I can say that while Final Stand may not be something I plan to play to absolute completion, it’s given me a new appreciation for Company of Heroes. Which is a good start for any spin-off.