a few tips: 1. 1st planet assaults only the 3 middle lanes (except for the boss). 2. Research 2-shot, then wall. When able, place all units on walls. 3. Research shooters to lvl 3, then grenadiers to lvl 3, then do the final shooter upgrade and then the same for the grenadier. 4. During boss fights sell unneeded units. ex: 1st boss attacks all five lanes at first, but when you defeat its tentacles you can leave only one walled shooter in a lane except the middle one. 5. Don't start expensive research on the last wave or boss fight. Sell as much as you can when you see the boss going down (you get a few seconds for that). Save for next planet 6. Waves attack middle lane, then three middle lanes, then all lanes. 7. Octog needs 3 3rd lvl shooters. Ratuin needs 2-3 4th lvl shooters + 1 4th lvl grenadier. Earth needs 4 4th lvl shooters, 1 4th lvl freezer, one grenadier. 7. Grenadier is always in front of everyone.
@Kopec Unit bank is on the left. Move your cursor to the middle tab there and it will open the unit bank. You can store any unit there - doesn't have to be rare ones you pick up.
@jrlyon Just to add to what he said: If you a less damage oriented hero, or you didn't spent enough points on might attributes (resetting points late in game is bad because you'll lose every point above 99) then you could still finish "the divide" challenge by doing everything jrlyon said AND increasing the health of your enemies. Just make sure you don't go overboard (+25% should be enough, +50% in extreme cases, keep yourself alive with hero skills) and everything should be fine.
Just finished that level with 20% hero (Ranger) strength and 14% commander's might. The added health allowed my hero to do more shots in some cases and that extra damage pushed me over the finishing line. Don't forget you need lots of focus totems fairly early on so that your towers could bypass the bosses' armor, or teleport your hero further up for those waves to make use of his Sandering ability (in case of Ranger heroes).
Even with all of the challenges solved I still can't find the last two journals. Why can't the game just show it to me on the map once I cleared the challenges? Does it have to be so repetitive and boring?
The manhole blowing level is great for leveling up all your marines to the max. There really should be no XP gain from endlessly respawning enemies. Or at least have XP for just the first couple waves or so.
I liked the part where i kept losing because i didn't have enough gold to fight fights that give me enough gold to buy cards that may allow me to win. Fun!
Oh yeah, not to mention the one strategy beats all for some magic types.
The leap in the 3rd chapter is just a time waster - no scenic view, no floating writing, no nothing! Very aggravating if you're doing Time Trial and have to waste those 30 seconds over and over again.
 "Ubooly & Friends"){kind=icon}
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Thank you and sorry for the triangles ;)