What were you thinking with Savage Spinach?
I know the title seems a bit like a personal attack, which isn't my style, but I'm genuinely interested what the thought was behind Savage Spinach's (SS) buff, and how it ever got past any testing. It's blatantly unbalanced. And though it's still not an instant win card, it literally combines multiple cards that cost nearly the same into one fairly cheap card.
Let's look at the cards that it makes obsolete (well, you can still play them for added power, but it's better to just play a spinach if you have that choice) or you can compare it to:
Berry Angry: A 3-cost trick that SS currently just took over in the patch. For 3 sun you can buff all your plants by 2, or for 4 sun you can do the exact same while having at least a 5/6 plant on the board (among other bonuses).
Onion Rings: A 5-cost 4/4 that sets plants in your hand to 4/4. Debatably very comparable to the other half of SS's buff. Though Onion Rings makes most cheaper cards tougher, it can also weaken certain cards. +2 strength will always work, and both affect all plants in your hand. Not a straight comparison, but the fact is that just half of SS's ability is pretty much as effective as this 5 card, but you still get a 5/6 plant on the board rather than a 4/4... for 1 less sun.
Dark Matter Dragonfruit: An 8-cost 6/6 legendary that wreaks havoc once it comes out with splash damage and massive cost increase for tricks. Why did I add this? As a zombie, I'd rather this come out than the new SS, regardless of the cost. They are roughly as hard to defeat, with a 5/6 compared to a 6/6, though with the very obvious Pea Patch combo, it's a 7/8 that can come out earlier than a 6/6. For that aspect, both can be blocked by cheap cards and dealt with. But once you deal with the Dragonfruit, the effects are done. With SS, you're dealing with a whole board of more powerful plants, plus the effect lingers for a whole hand afterwards. If you leave SS the way it is, you may as well change the L50 icon to SS instead of the Dragonfruit.
Intergalactic Warlord: The 5-cost 2/2 zombie version of SS. OK, so the zombies already have a unit very similar to SS. It doesn't need a particular type of evolution, and lasts the whole game instead of the remaining cards in 1 hand. But it costs 1 more sun, and is a 2/2 that only buffs to a 3/3! Maybe if SS was something around a 2/3 base (4/3 buffed) it would be a closer comparison. But a 3/3 compared to a 5/6 or potential 7/8? I don't think anyone has to debate which one is better. Though it's easier to bounce the Warlord or put it in a grave to get its effect again, I'm mostly pointing out how unbalanced SS is as its own single card.
I haven't mentioned the 'added' cost that evolution cards have, because although they do require 1 other card plus some sun, there are many additional benefits to evolutions that generally outweigh the drawbacks: they 'fully heal' the spot they were on, often used on plants that were already near death; they can be placed on a full board, not needing an extra spot; they can potentially be played in the water; they often have stronger effects earlier in the game, in this case on turn 4 even without extra sun. So you shouldn't really say that it 'costs' 5 or more sun to compare, unless you're comparing against other evolution cards.
SS is still beatable (for the most part). But the point of this post is asking why some random super-rare card, not even a legendary, got so unbalanced against other cards. The only upside of it not being a legendary is that only 1 card can possibly summon them in game rather than 2. The problem with SS before that made it rarely seen was because other leafy cards were pretty lackluster compared to other synergy options, not that SS was ever inherently weak. Slightly buffing other leafy cards, or adding new ones, would have been better.