Chapter 133, "Level 2 Village Buildings", is the clearest early answer because Gugu Bird House finally turns buildup into a real advancement. The chapter turns that into something concrete by moving from Regardless of potability, she seriously considered the Bathhouse.

Chapter 212, "Preparations (Part 1)", is the clearest early answer because it turns Gugu Bird's situation into a concrete plot event. The chapter turns that into something concrete by moving from It was no exaggeration to say that the announcement got everyone out...
Chapter 193, "Visual Sharing", is the clearest early answer because it turns Sharing Bird's situation into a concrete plot event. The chapter turns that into something concrete by moving from After ensuring the Clark Crown Cat had merely been under hypnotism,... to How can he be so foolish." Others only asked what the Pet Beast's....
Chapter 90, "Thunderclaw Bird", is the clearest early answer because it turns Thunderclaw Bird's situation into a concrete plot event. The chapter turns that into something concrete by moving from Thunderclaw Bird, a General-level Pet Beast. to But for high-level Beast Tamers, the more developed their brain....
Chapter 91, "I'll Help You!", is the clearest early answer because it turns Thunderclaw Bird's situation into a concrete plot event. The chapter turns that into something concrete by moving from The Thunderclaw Bird's strength should have overwhelmed the... to When would it ever become so powerful....
Chapter 762, "Flame Joy Bird (Two-in-One)", is the clearest early answer because it turns Fire Dance Bird's situation into a concrete plot event. The chapter turns that into something concrete by moving from Where exactly is the true body of the Fire Dance Bird!" Fire Dance... to With the movements of the Fire Dance Bird, clusters of stunning....
Chapter 443, "Fire Suppressing Bird (Combined Chapters)", is the clearest early answer because it turns Fire Suppressing Bird's situation into a concrete plot event. The chapter turns that into something concrete by moving from The Pet Beast Battle Field at the Moting Hotel is a public area,... to As both sides prepared to start, Yaobao stepped forward..
Chapter 827, "Auction 1.", is the clearest early answer because it turns Gordons Auction House's situation into a concrete plot event. The chapter turns that into something concrete by moving from Though Alec already had his suspicions about who was responsible for...
Chapter 369, "Ferrol Annual Market Fair", is the clearest early answer because it turns Of's situation into a concrete plot event. The chapter turns that into something concrete by moving from They remembered when they first saw it.
Chapter 730, "Refresh Rate", is the clearest early answer because it turns Was's situation into a concrete plot event. The chapter turns that into something concrete by moving from Meatball could control his weight and Pepper seemed to have the...
Chapter 639, "I will help", is the clearest early answer because it turns Of's situation into a concrete plot event. The chapter turns that into something concrete by moving from What do you mean by no? to That would be nice." Then he looked at her, "Although I didn't stay....