Tips and Tricks
On the topic of income. I would recommend that as soon as possible you unlock harvest guild units and armaments. The synergies are literally get more zar per level, per boss kill, more interest and stuff like that. I almost always have (at least) two of those bots in my build.
The free reroll is excellent at saving zar. Try not to get sucked into pointless rolling if you don’t have lots of cash to spare – just use the free re roll every time you level.
I’m sure you already know, but it’s worth saying – synthtech is difficult to build right now. It’s great endgame if you manage to get there, but its not easy. Guns are easier. I often go rifles if possible because more bullets per shot is great.
In terms of perks, of course grid capacity is pretty much an instant pick. extra zar earnings is also quite good. One other perk that I always, always pick if I’m running guns does something along the lines of reducing your guns clips to 1 ammo, but reducing reload time by half. Think there’s another effect that i’m forgetting as well. Why is this good? Well, you can get it twice. Yes, instant reload guns, in effect infinite clips.
Mercenaries are very good, but have negative synergy so I generally only ever run one unless I have insane money and a need for a second. Do not underestimate the mercenary tracker. There is a reason they have a negative synergy – every single one gives a powerful buff to the entire grid. The omniloader is generally the best, as others have said. Every level of it gives you an extra grid capacity and movement speed.
As for some info for the upgrades so you can decide whether they’re worth it. weapon and unit shop inventory barely need to be said, 3 instead of 2 choices per reroll gives you more bang for your buck.
Nest tracker allows you to find nests easier = kill more bosses = more perks.
The tier 4 & 5 roll chance are great, but quite expensive.
Kaizen machines (units) have a synergy that (from memory) reduces reload and synthtech cooldown time. Can be useful in either build.
Self intelligent weaponry – bit of a variety in the actual weapons, the synergy is that your grid will all focus fire bosses and have a chance to call lightning on hit. Naturally, focusing bosses means you may not be clearing the mobs around you.
Defense response – weapons that are mainly an aoe centered on the bot, or radially fired bullets. The synergy adds bots regen to their weapon damage (gun or synthtech) and as such are naturally good when paired with repair bots.