At level 13, my first sushi cat Nom-Nom-ed sweeping through almost the entire sushi field. Unfortunately, he was so huge that I had to watch him bouncing among the platforms for more than 10 mins ...
build a few towers nearby the village so that when enemies reaches there, I can still swap gems from other locations to there instead of making more expensive gems.
low leveled gems are a waste of mana eventually. I usually create the highest level of gem that my mana allows me to create, say level 4. Then upgrade my mana pool until the gem barely holds off enemies, get another level 4 or a level 5 gem. Make sure to have 2 level 5 gems before starting to create level 6 gems for survival reason. Then I keep upgrade mana pool until I am confident to make a level 6 gem. combine 2 level 5 gems to make another level 6 ...
Repair station is what I usually get for defence, however, I prefer to build some energy relays and miners in speed mining mode. Cost for a repair station: 300, a relay(100 hit points): 20, a miner: 45. Extra miners yeilds minerals as revenue at the cost of losing energy relay. Besides I can reach my goal faster this way. Not a bad tradeoff!
Missile turrents are so useful. Not to mention each fully upgraded missile turrent costs much less than a fully upgraded THEL, missile turrents are the best when dealing with motherships and explosives. Think it this way. Instead of getting a THEL and an energy store, build a missiles and a bunch of miners. Missile turrents gives as strong protections to your base as THEL do, while you will have more miner mining minerals. Each missile does cost meager amount of minerals (5?), however, its 550 splashing damage can take down motherships in no time at all!
 "Sushi Cat"){kind=icon}
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