WARNING: the following contains spoilers for Episode 36 of That Time I Got Reincarnated as a Slime, now streaming n Crunchyroll.
Surviving in an isekai world isn't easy, but Rimuru Tempest hasn't just survived -- he's thriving. As the world's strongest slime, he has an entire monster nation under his thumb and, more recently, all the power of a Demon Lord. But even that might not be enough against his strongest foes. It seems there's always a bigger fish, even now during the mid-season finale.
Rimuru won over the mighty Milim Nava to his side, and he fought the holy knight Hinata Sakaguchi to a standstill in an intense duel. But now, despite becoming a True Demon Lord himself, Rimuru might be in over his head, and Demon Lord Clayman is tightening the noose.
Milim Nava Becomes Rimuru's Biggest Headache (And She Brought A Friend)
Rimuru has done the impossible. He took on an entire Falmuth invading force and won, absorbing thousands of human souls to fuel his transformation into a True Demon Lord. Once Geld, Hakuro and the others finished off the remaining Church warriors, peace returned to Rimuru's kingdom, and he revived the fallen as promised. But the dust barely settled on this battle before another feud erupted. This time, it's the Animal Kingdom, Eurazania.
Rimuru was knocked out for three days after reviving his friends and upon waking up, is warned that Demon Lord Milim assaulted the Animal Kingdom without any clear provocation and fought Demon Lord Carrion at full strength. Milim's previous displays of power are nothing compared to her battle mode, which allows her to blast the terrain apart with an apocalyptic energy attack. Worse yet, Milim brought along Demon Lord Frey, a Valkyrie-like Demon Lord, and the two of them were too much for Carrion to handle.
Their battle has created a large-scale refugee situation for Rimuru's kingdom, and while he's willing to shelter those in need, the real issue is the devastation of Eurazania. The entire kingdom fell to Milim, who seems to be operating with Frey on behalf of Demon Lord Clayman, who's been working in the shadows this entire time. Nearly every problem Rimuru has faced can be traced back to him, and it seems like he can no longer be ignored. He must either destroy or win over Milim once again, and deal with Frey as well. Given Milim and Frey's strength, though, that's easier said than done. Rimuru might finally be out of his depth, even if he just became a True Demon Lord himself. But, thankfully, he has allies.
Diablo & Veldora Join Rimuru's Party
No one in Rimuru's forest city is strong enough to take on Milim or Frey, not even Benimaru or Geld, but he does have other friends to call upon. Once Rimuru slaughtered the Falmuth soldiers, he offered up their dead bodies and summoned a mighty primordial demon, who in turn took care of the Falmuth mage Razen. Now, Rimuru summons the demon once again and, with his vastly enhanced magic stores, grants the demon a name, Diablo, and an upgrade. He swears to be Rimuru's loyal minion and ally, not even asking for anything in return. On the face of it, at least, Diablo is the ultimate servant, but he is still a demon, which means this could be a ruse. Rimuru had better hope that Diablo isn't conning him, because Milim and Frey are still out there.
Finally, Rimuru returns to a certain nostalgic cave, where the spell containing Veldora the storm dragon has just worn out. Rimuru is ready to bring back his old friend and grants Veldora a cloned body of himself, which Veldora reshapes into a brawny, blond male form. With Veldora back, Rimuru can only hope that he'll agree to help him scare off the other nations with his might. Rimuru is making more enemies than he can handle, so a draconic deterrent is just what he needs. At least Veldora owes him a favor, which should keep this reborn dragon in line.