Early game strategies
In Dota auto chess early game optionality is key. You want to be open to get whatever units are available. If you don’t get immediate 3 of a kind to get strong unit, save units that can be part of strong late game strategies. My personal top 3 choices at 1g units include
1 – Enchantress
2 – Batrider
3 – Shadow Shaman
Batrider and shadow shaman are weak and uncommon early game choices, but 4 trolls combo is perhaps the best species combo in game. However it is reasonable only if you have both lvl 1 trolls upgraded early, and you should usually eliminate your early troll plan if it doesn’t improve.
After picking and deploying your first hero look what others have picked. Most people don’t eliminate their first unit immediately after round one, but continue collecting similar units. If 3 or more players have enchantress, you should abandon druid plan unless you get good start in first 3 rounds. If less than 2 other players have warrior or mech units those strategies are more likely viable. Always be ready to eliminate any of your units and end round with the best set of units available.
Round 4 is first fighting round and if you want to get winning streak started you need decent lineup. Classic good lineup is 2 mechs and a goblin (or 3 different goblin mechs). If you get one of those level 2 early it is both cheap (for good interest gains) and effective (for win streak). If you get lucky lvl 2 treant that is also likely to result in a win streak. Other good combinations include 3 different warrios with 2 orcs buffing juggernaut. Any other good lineup is driven by lucky early upgrade. If you go to PvP fights with bad lineup look for losing streak based gameplay.
Before interest is possible keep all your money invested in units so you have maximum possibilities to hit 3 of a kind early.
After round 4 players have gained 15-16 gold. At this point interest is available for the first time. At this point game gets more interesting since players total gold gains start to differ rapidly. At this point you can either keep many fairly costly units in your reserve slots to “draw” into strong level 2 units OR keep almost empty reserve and gain 1-2 extra interest per turn. Different species combinations want to do different things.
Win streak + Unit building
If you had a good Druid based start and have either lvl 2 treant or both lvl 2 enchantress and lvl 2 furion you are likely to get a win streak going. Each round win will get you one bonus gold and win streak will eventually get even more. The problem with Druid strategy is that they don’t have any late game synergy and all lvl 3 druids, except lone druid are mediogre fillers in typical final lineup. For this reason druid player should keep options open to build other strong units in addition to druids and get some other strategy started. If you are not playing druids you may choose thisstrategy if your lineup is easily upgraded.
Look results that others players have as well as your own. As your lineup is close to losing in your table OR SOMEONE ELSE’s it might be time to spend some gold to get extra chess on board or a shop refrest to get extra unit upgrade. NOTE: you may lose a fight in someone elses table without losing your win streak. This is important signal to note and react accordingly.
Win Streak + Banking
If you have good early game units but are unlikely to improve your lineup drastically with new level 2 units, you should keep reserve so empty that you get maximum available interest. This happens most often with mech lineup, since lvl 2 clockwerk/tinker/bounty + 2 level 1 mechs/goblins give so good bonuses that you don’t gain by replacing them with typical lvl 2 unit options. Those 3 unit lineups cost 5-6 gold meaning you can get first interest round 5 and after that you can afford the extra units as you get slots for them.
Lose Streak and Banking
If you didn’t get good mech or warrior lineup or strong lvl 2 units early you are likely to start losing pvp rounds. Avoid keeping many 2g or 3g units in reserve and instead look to maximize interest. Try to build some endgame units, for example lvl 2 crystal or trolls. The reserve trap is at its highest with assassins or warriors as there are many 3g cost assassins and endless different warrior units. Very often you keep pairs of 3g assassins ready to get that third one for upgrade and while doing so lose 2g per turn that would have accumulated for so much faster levels and better late game units later.
Using one of these strategies should get you to 10+ gold income fast. That means you have one of the largest amounts of gold to spend for level ups and units.
Playing good midgame means you usually have one of the strongest economies going to late game. That means you have gold and levels to build decent to strong late game lineup.
If things go bad and you bleed life too quickly during midgame or early in late game it is important to spend your gold reserve before dying. I call this “Midnight Oil”- strategy. Good time to use it is when you have around 30 life left and lose close to 10 life per round (this is where skill comes in, sometimes you need to start bit earlier when taking more damage and sometimes you can squeeze in few high interest rounds more if you only bleed few life per turn). Midnight oil strategy means using gold reserves to level up in order to get one extra unit slot and refreshing shop to get required unit upgades faster. Downside is that you will lose your interest income and often slow down your late game progress detrimentally. Upside is that you sometimes get strong enough 8-9 unit lineup to get you to top 3.
Proper late game
If you reach level 9 with 50g in bank you can play normal late game and try to get as good lineup as possible.
Most of the time you have some units from early game that you want to use. Any non-Druid level 3 upgrade is likely to be worth it in final team. If you have druids, you may want to eventually call back Enchantress and Furion lvl 3 when you get better units, but that usually happens at level 10. Most 3g units at level 2 are something you want to use in final lineup and you should aim at their class and race benefits instead of building full teams of units to get their race/class benefits.
All race/class benefits are not equal and you should usually aim at the best lategame upgrades using minimum number of units to do so. Avoid race/class benefits that require you to have huge number (usually 6) of same type. The reason is that by getting 6 warrior benefit for example you essentially use 3 inferior units to give small boost to your 3 best warriors instead of tabling your best options. Are you 4th, 5th and 6th best warriors really better than lvl 2 4g units or level 1 5g units you could use instead? Also the boost that you get with units 4-6 is usually smaller than for example the boost you would get from 3 warlocks, 2 undeads or even 2 beasts (again first 2 undeads or first 3 warlocks are often better than 4th, 5th and 6th best units of your primary type). Also most race/class benefits boost only their own race, which is bad since you might have strong unit of other class accessible but have no benefit for it.
Some of the best/ easiest race/class benefits and things you might want to try to get in late game
1 Crystal Maiden lvl 2+
Crystal Maidens arcane aura is so good and high impact that it is like a class benefit. It allows your Tidehunters, Dooms and Disruptors cast their ultimates before opponents and that initiate sometimes means your opponent is not casting those skills at all. It got nerfed recently so it might not be as insane anymore.
This is only race combo that is both hard to assemble and worth it. 4 Trolls give your whole team +35% attack speed improving all your units instead of only Trolls. Since attacking also makes mana for your units 4 Trolls also provide unique mana regeneration benefit that would otherwise be accessible only with Crystal. It is noteworthy that 2 of the 4 trolls are 1g units and weak even at level 2 meaning that building trolls is usually a strategy that is losing many rounds before assembling the combo and is usually played with losing streak midgame strategy. Also Trolls only work if there aren’t many players building them, since you would want to get at least one of the 2 lvl 1 units to level 3 and Witch Doc and Troll to level 2 in your final lineup.
In dota -5 armor increases physical damage against enemies by 30%, if I’m right. This benefit usually takes only one new lategame unit to get and increases your teams DPS by 10-20% and is worth getting in most games. Lategame units that help you getting this benefit are Lich and Necrophos. Lvl 2 Necrophos is almost always good and lvl 1 Lich is almost always worth playing if it gives you additional Undead boost.
You should almost always play Tidehunter when you get it, so first level of magic protection only costs building one additional Naga unit. Any lvl 2 upgrade is usually worth it in final lineup.
20% Lifesteal to all of your units is very good. Lifesteal is not easily accessible in this mode and is very good with physical damage
Having 3 mages reduce opponents magic protection greatly, giving team that has heavy magic damage 15-20% damage increase. As mentioned earlier 6 mages is rarely worth it, since you shouldn’t have many 2-3g mages in reserve waiting for upgrades in mid game so your 4th-6th best mages are usually a lot worse than your top 3.
All these combinations are great, because they boost your best units regardless of the types that unti has. That said one additional lategame combo that can win games:
Carry unit + Items
As seen in DPS chart most damage in most lineups is done by few heroes. Items can greatly increase DPS of some units and you should boost the best units with most items. Lvl 3 Lone Druid is only Carry-worthy Druid unit. For other races most 3g lvl 3 units are good for carrying items. 4g lvl 2 units are most accessible carry types, my usual choice is lvl 2 Templar Assasin or Troll.