I feel like this game has quite a lot of potential, especially with the nice puzzle aspect of core optimizations, but falls short because of the bugs (I recently had to do a hard reset because one of my reboots reset my decryptions, but not my ability to do them, so I had only one core, no efficiencies, no global bonuses, etc. Plus, as others have commented, the core shapes will sometimes get stuck in improper locations and require a refresh, among other things) and balance issues (higher tier decryptions have global bonuses so powerful that most of the research upgrades are pointless, especially given how long they take). The fact that this game hasn't been updated for about a year and a half does not give me much hope, but I think that this game could really be something great with a little more polish.
Additionally, the Decryption animation seems to still be running and rendering even when the decryption tab isn't visible/selected, as the slowdown from having multiple at once persists throughout.
Refreshing the page with a Decryption active will allow you to run multiple decryptions at once, which tends to lead to the game slowing down heavily (especially when it's not the only thing running on the computer), which makes many other portions of the game (the shape puzzles in particular) misbehave in odd ways (floating shapes, shapes changing into others whilst keeping their color, overlapping and core layout loading issues, etc).
A rather disappointing glitch to this otherwise great game: I was considering buying premium if I had enough Kreds, but clicked the button to do so in the middle of an endless run, and when I closed the "You need more Kreds" popup, it had ended my run and taken me to the level select screen. Thankfully, I wasn't far along in that run yet, but still annoying. Other than that, great game! I especially like that the powerups themselves don't require Kreds.
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