The Weakest Summoned Beast? I Become an Emperor by Merging Plants

[Golden finger, plant army, dungeon runs, no mindless harem collecting] Monstrous beasts invade, and the entire world falls. At this desperate hour, humanity awakens summoned beasts to fend them off. The protagonist, Jiang Xu, was born into this world and, when his summoned beast awakened, he also recovered memories of his past life and gained access to a fused version of Plants vs. Zombies, with some changes. Starting with a single seed and relying on the System for everything else, he embarks on a laid-back journey of leveling up. A thousand years later, you’ll see Jiang Xu establish a Plant Empire, with a giant obsidian beast unleashing an atomic breath at his left hand, and a plant version of Wisadel unleashing “Explosive Dawn” at his right... A new game: Plants vs. Beasts.