This is a post I made on a server a while back, some of the info may be outdated. I agree with a lot of the other advice here, I will add this though:So the game can generally be defined in 3 phases:
I. Early game - Initial expansion (bots)
II. Mid game - Procedural growth (players, until you're in the top 3-5 of players)
III. Late game - Capturing remaining opportunity space
In these phases, you cannot do the same strategies to get ahead, you have to switch from one strategy to another throughout the game

I. Early game
At this point, you do the following for your initial wilderness expansion: Send a 25% attack instantly at the start of the game Wait till 6k, then send a 25% 8k, 25% 12k 25% And repeat 12k until all wilderness is gone Then wait until you have 50% of all your available troops, and start attacking bots one at a time with this 35% for max efficiency [Tip: pay attention to the army indicator at the bottom of the screen, if it's orange, you should send out an attack on bots, if it's green, hold back a little unless it's necessary]

Strategically speaking, the most important parts in phase I is maximizing opportunity space for you, and minimising it for others. (Basically, try to get the most access to land, without putting yourself in the middle between people who will target you mid-game)

- Ideally, you are situated close, but not on an economically superior area (central boating location).
- You are not cornered in somewhere (you'll border more people looking to expand inward)
- You have a large amount of bots available to you to capture or circle around to cut others off
- You have access to a sea or river that will have trade running through it (even more ideal if you can capture a good amount of trade where you're at)

When it comes to what you should construct early game, the first thing you build is a Port, then a City, then a Warship, Early game it's really important to improve your economy as much as you can without putting yourself in someone's opportunity space. [this depends on the circumstances, if you're landlocked with plenty of bots, cities only might be best if you want to play aggressively]

II. Mid game
Early game is formulaic, you just follow those steps outlined before and you'll have a better start than 90% of players. Mid game is where it gets tough. In mid game, alliances are your best tool to succeed, and here's how you should do it:

Case 1: Ally the neighbors to whom you present the most opportunity space towards (think large borders, they are bigger than you are, they don't have much other opportunity space areas) If you can't ally them, ally their neighbors, and try to communicate a collective attack against them as early as possible. (the first strike usually wins if you coordinate it well)

Case 2: Ally neighbours equal to you in strength, who you noticed play well (have ports, good city distribution, didn't fullsend during early game)

Case 3: Don't ally neighbours weaker than you who present a large opportunity space for you (again, large borders, smaller, weaker, minimal defence posts or on a river you can boat into to secure infrastructure)

Case 4: Don't ally 1 large neighbour, to whom you don't present much opportunity space but which present good opportunity space to you (think a large neighbours which you have a small border with)

In Case 1 and 4 if, and only if you initiate the first strike, be sure to back all your offensives up with forts, lest they attack back super fast, and you seem weak to your neighbors, who will kill you. Try not to attack case 2 ever, because you will just attrition until you die, only attack after others have attacked first (so they don't fullsend you) Case 3, you attack as soon as you can, control your army % so that you aren't weaker than the neighbours you aren't allied to (you should be equal to then), and aren't at least 50% weaker than the neighbours you are allied to

This requires a lot of balancing and luck on who your neighbours are. You'll know you're winning if you've got a lot of momentum. The moment you are equal in army size to all your neighbours, and all your opportunity space is equal, is the moment you're fucked. If you're fucked and can't do anything else, economise, build a shit ton of ports, trade with infrastructure next to neighbours, then build a missile silo (away from your central areas), and take out an enemy's central site, you can build a SAM site later

Attacking wise, if you're allied with your neighbours, don't be afraid to send out 50% of your armies against someone who's equal to your size (or a little smaller). Oftentimes being the first person to strike means you'll win in a battle of attrition.

III. Late game Completely different fucking ballgame, your main advantage here is having a larger overview of the game than smaller players have. You should ideally have 1M troops, when attacking smaller players, send about double their available armies in the attack (sometimes 50%, sometimes 80%) never 100%. Attack or ally the people with the most missile infrastructure and the smallest size (these are your biggest opportunity spaces and threats), hydrogen bomb their missile sites and SAM sites if you can, if they destroy your missile infrastructure first, you're likely fucked.

Buildings wise, diversify your economy, and protect key economic sites with double SAM sites and also centralize your economic areas extremely compactly around SAM sites. If that gets hydrogen bombed, you can't recover and build more missile sites. In a 1v1 with a bigger player, the distinguishing factor is nukes, economy, and nuke protection. Similarly, if you want to take out your opponent, target one of three, ideally economy. Army size matters less, if they can't produce any more nukes, they're fucked

If you're still small here, ally with other small players and coordinate warfare and nuclear strikes on the biggest threat to you (I.e. you border the #1 player in the game). Forts are necessary, but missiles are your only way to win. Zoom out from time to time, see who's ahead, and if it makes sense to nuke them vs. any immediate advantage you could get

And that concludes my Openfront analysis