Scalebound always looked interesting to me. Even the jank demo trailer they put out had me hooked. I like seeing the difference in scale between humans and giant creatures. Love me some Godzilla, Monter Hunter, Last Guardian. Big creatures are cool, and fighting alongside them and against them is also cool. Titanfall 2 should get a shoutout here.
Lineage Eternal, Lineage 3, also caught my eye. It was like a diablo-esque game but you could draw spells on screen or something to use them. It's been a long time since I've watched the in-dev vids and stuff from beta but it still looks good checking on it again now. It's since been canned and is now "Throne and Liberty" and not associated with the Lineage IP anymore I think. There were many iterations of a Lineage 3, Eternal though was my favorite.
Too Human is the last one I'll bring up. The first game came out after being in development for like 10+ years. I think it was the longest dev time game that actually released when it did. But it was reworked and redone so many times it lost a lot of the promised features. Even like a year before launch they reduced co-op from 4 to 2, and pretty sure they changed how healing worked or they dropped a class or something. Only one class could heal with the game that released.
Anyways it was supposed to be a Trilogy, that's how it was advertised. It was developed in Unreal 3 and the devlopers, Silicon Knights, had said they did not receive the entire engine from Epic when they got rights to use it. So, they had "altered" it enough that they deemed it its own engine. And when it came time to pay Epic they did not. Lost that court battle and the studio shut down afterwards. Silicon Knights worked on some good games. Legacy of Kain, Eternal Darkness, Twin Snakes, and my mediocre gem Too Human. Shame I'll never get to see the end of the story. Sci-fi norse mythology, very cool take on it all.
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^ poster from the proposed second game in the trilogy