either take all the rewards back and give a refund, or let everyone keep their stuff. by taking the coins back but not items, you reward people who bought it and spun them all quickly. not very fair.
As a fully f2p player for 1 and a half years I can say that this game is definitely playable with no cash spent. It will take a while to get a decent deck but if you get into a guild you can get SP much faster with gold from raids and wars.
I did not beat the final boss with no bombs used or no damage taken or with the warp core. I used antimatter bombs to take out his arms (melee weapons are pretty stupid for a bullet hell game) and the double shield was pretty much necessary.
For farming cash use homing lasers, 2 with split, 1 with poison 1 with affliction (poison and affliction doesn't stack) and collectors. For the first 20 levels you can pretty much breeze through without a problem. For super fast cash get antimatter bombs and kill the second boss by spamming them, it gets you tons of cash in seconds. For survival mode, use the farming build but with defense lasers. I use the green hull for lots of focus, I got up to level 46 on my second try. For level 25 I used flak, split, homing, double shields, red hull. However it was very difficult so I suggest using homing lasers instead. The attack where two of his orbs sit next to you, don't move or else you'll be hit. Then when the bullets pass hit focus and dodge the wave from him.
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 "Tyrant Unleashed"){kind=icon}
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