That is the solution to the puzzle. It works. There is no other way to solve it. If you can't get upper left from there, you are probably missing how to chain walk across gates with key. It is the same technique you use on key flower to get to the flower.
You have to open the gate, take a step back to reset the spell, and then use it.
That's what the note in the gate maze telling you to turn back to reset spell progress tries to explain, and why that note is in the gate maze.
Which bush exactly? There are a few choices! I posted the step shapes for fire in another comment. The third row is fire upright. You can't get that bush on the leftmost side of the map from the go back to trophy room nook below. You can see no upright fire shape fits.
If you are talking about the bush just upper left of the center star with two blocks sitting on it, you can't pass it. But you have already solved the hardest 2 parts of the puzzle if you have reached that nook before the tower of five blocks comes crashing down behind you. The solution is right there, just not through that bush.
Key fire was probably my favorite trophy overall for where I was in the learning process. It also took me a while, although I got hung up on two different steps.
General Hints: It is way, way easier to attack the trophies when you have a visual reference for the step shapes you can fit in an area. Here are the possible step patterns for flip (purple) and fire (red), regular and inverted. Lighter square is start, and darker square is finish. I also included the chain flip into fire.
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Hint for Key-Flower and other lower left key trophies.
I got stuck getting started on some of these. Rot13(Yrnea ubj gb punva tngr pyvzof ol fgnegvat n jnyx va gur evtug cynpr fb gur xrl npgvingrf zhygvcyr gvzrf jura lbh arrq vg.) To read the hint, please copy and paste into an online Rot13 cipher decoder.
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Hints for G-Flower-Flip. I hit a point in this puzzle where I stopped having fun and would have appreciated a few concrete “You are doing this right/wrong” because there are a lot of things that have to come together just so and it can be a while before you realize you have softlocked.
First hint, in plain text because it doesn't give anything away. If you are stuck on G-Flower-Flip, drop it for a bit and solve G-FIRE-FLIP instead. It is not one of the trophies, yet G-Fire-Flip presents the same conundrum as G-Flower-Flip with the benefit of being harder to softlock and having more possible solution variations. By taking away your ability to destroy scenery with flower and reducing the complexity to obtaining the single star you can't get as human-fire-flip, it puts focus and clarity on the single major problem.
Hint 2 for G-Flower-Flip Rot13(Lbhe frpbaq fgne nsgre gur gevivny fgne fubhyq or gur hccre yrsg. Gb nibvq ybat-qvfgnapr fbsgybpx, lbh arrq gb chfu gur bar npprffvoyr abgr vagb gur pragre fdhner svefg guvat. Nagv-sehfgengvba, lbh pna fgnfu vg ol chfuvat vg hc vagb gur “pbyyrpg rirel fgne gb jva” abbx ol gur gevivny fgne naq gura fgrccvat hc ba gur pbyyrpg abgr gb chfu vg qbja yngre jura lbh arrq vg.)
Hint 3 for G-Flower-Flip Rot13(Gur frpbaq ybat-qvfgnapr fbsgybpx vf sybjrevat pregnva fdhnerf va gur ebj nobir gur ubzr ebj orsber lbh frg hc. Vs lbh ner fghpx naq qba’g xabj ubj gb trg fgnegrq jvgu guvf chmmyr, nofbyhgryl SVEZ ehyr xrrc nyy sybjref rdhny gb be orybj gur ubzr ebj hagvy lbh unir “cvpxrq n qverpgvba” – lbh jvyy xabj jung gung zrnaf jura lbh trg gb gung cbvag. Bayl gura jura lbh unir guvf fcrpvsvp bowrpgvir jvyy sybjrevat nobir gur ubzr ebj znxr frafr.)
Hint 4 for G-Flower-Flip Rot13(V pbhyq trg rirel fgne jvgu bayl rvtug gbgny hfrf bs sybjre vs hcevtug be gra vs V jnf vairegrq qhevat n pregnva znarhire.)
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To the developer, EpicPikaGuy:
Absolutely fantastic puzzle design. The different star directions and open puzzle field allows new players to compartmentalize on regions and bring previous victories forward unlike many "grindy" high-reset block pushers which feel more like chess plotting moves in advance. The only change I would suggest is modifying the trophies to require G-Fire-Flip before G-Flower-Flip. G-Flower-Flip is a major difficulty spike otherwise. See image.
