AC Guevara is very tough, yeah. It's not as extreme an escalation as something like Gradius III, whose 1CC utterly dwarfs its two predecessors'. If you can 1CC Ikari or Dogo, you can probably 1CC this without too much more trouble. But as Obada-san's last word (AFAIK) on the subgenre he helped popularise, he goes out with a vengeance.
Really cool guy - read blackoak's
customarily beautiful translation for many insights and anecdotes on the arcade action industry - like how DECO shoplifted Ikari wholesale to create Heavy Barrel.
There's also a prestige element not in Ikari or Dogo, namely POWs. All too easy to splatter them while bastarding the enemy. Meanwhile, enemies won't target POWs, but they
will mow straight through them to hit you, punishing indecision. An all-POWs run, even not going for score, would surely be a hair-raising feat.
For survival, our own GGA_HAN rates it about even with Ikari, having one-lifed both. I found Ikari's no-miss slightly easier than Dogo's, but also a lot cheaper, owing to those
goddamn beacons. We'll see I guess! I can tell you Guevara's first boss (super heli) blows his remaining four colleagues out of the water. I was aghast at his relentless barrage being merely the first encounter, but he's very much a feint.
It should also be noted, in some ways, Guevara is kinder than its predecessors. Your basic shot is wickedly fast, for one. And vehicle exit i-frames?
What falsificarous sorcery is this?! Ikari don't give a
fuck - if you wait too long to bail out of an exploding tank, the only mercy you'll receive is that of the grave.
Just like Ikari's tanks, and to a lesser extent Dogo's armour (useful in the first half, rapidly obviated by the sword in the second - don't ever drop your sword in Dogo), learning how to leverage Guevara's tanks will break once-thorny swathes of ground open.
New to this game, if you exit your tank - say, to conserve its fuel, because in the Obadaverse, any vehicle that runs out of gas will explode - a grunt will eventually rush in and attempt to steal it.
Nice try bitch 
There's a trick to exploit, here. If you're running on fumes, let them have the tank - then blast 'em right out of it. Enjoy a fresh tank of gas, they must've brought their own.
All this said, Guevara's grenades suck ass.
Not fit to shine Ikari/Dogo REDSPLOSION boots. Obada giveth and taketh away! Then again, enemy grenades now suck too!
I remember joking with my older brother and cousin that in our family, this game might as well be called "Pol Pot Daisakusen."
But we all agreed there's no more ignominious fate for its real-life inspiration than to have his likeness bought and sold by capitalist pig-dogs, so it all evens out.
ACA ver seems the line's usual superb quality so far. Already hugely enjoying the button config - unlike Ikari and Dogo, where autofire's not really a factor, here it's very handy to have dedicated manual/auto buttons. Your base MG, while short-ranged, is devastatingly powerful if rapid-fired. So are the special weapons, and tanks - but
those have limited ammo, so you don't wanna go ham.
Anyhoo I'm very pleased, between Hamster and M2 my plate is full up for years to come, if not longer.
This past gen's been a real treat for arcade gaming on console. Seems there's no end in sight just yet, either.
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Sounds like you ran into a bonus stage miniboss, in Victory Road - I'm guessing that flying three-headed turtle prick, who's very difficult to tell you're damaging (unlike his colleagues, whose eyeballs and mandibles explode in 'orrible detail). I wonder where that design's from, Space Harrier II (MD)'s first boss is practically the same.
He's also by far the game's nastiest boss, unless you know how to neutralise his zako (there's that Type A supremacy again!). I currently fight three midbosses, none of them the turtle prick. The bonus stages can be lifesavers, in a way... entering them will effectively nuke the screen, the tradeoff being you've got the kill the boss to escape, of course. None of the ones I fight are all that tough provided you've got Red grenades.
(Just like Ikari, if you die in Dogo and lose your powerups, you are in a world of shit
easier games to no-miss than 1CC with deaths)
)
Incidentally, there's a middle version included in the ACA release along with those two, which AFAIK was a developer board.
How about I hotwire my grandma's rotary phone to the pad? That'd be an improvement tbh - at least with reliably-spaced clicks, there'd be some synergy between the controller and the onscreen character.
Seems just about anything that Makes You Move Like An Animal AND/OR Make Noise Like An Animal is fertile ground for DEVILS INCLINATION 
Also, if you were burnt this time last year by the crummy Ikari III - this is the real Ikari III. 
