Hollow Honeycomb

Extra Honeycomb Pieces are collectibles found in Banjo-Kazooie, Banjo-Tooie, and Banjo-Kazooie: Grunty's Revenge. Usually hidden in hard-to-reach places throughout the games' worlds, collecting a certain amount will increase Banjo's maximum energy capacity by one honeycomb.

Banjo-Kazooie
In Banjo-Kazooie, collecting six pieces, regardless of location or order, will extend Banjo's energy. There are two extra honeycomb pieces in each of the nine worlds and six in Spiral Mountain, collecting 18 of the 24 pieces will raise Banjo's energy bar from five to eight, however the final six Extra Honeycombs will not raise the health to 9 and only serve as extras. Two of the pieces only appear upon hitting a Honeycomb Switch, one of them in Gobi's Valley and the other in Rusty Bucket Bay.

In the Xbox Live Arcade version collecting all them still does not give you 9 health but it will unlock an Achievement.

Banjo-Tooie
In Banjo-Tooie, different worlds have different numbers of extra honeycomb pieces. Instead of collecting six, Banjo must collect a certain number defined by Honey B (which starts at 1 and increases by 2 each time) and bring them to her hive in exchange for an extra honeycomb. Each time he exchanges honeycomb pieces, the number he must collect for the next honeycomb will increase. Once Banjo gives up all 25 pieces, his energy bar doubles in size from 5 to 10. The energy bar increase affects all playable characters and transformations (excluding the Snowball transformation), although the total bar size will differ (for example, the Washer transformation always has one more honeycomb than BK).

Banjo-Kazooie: Grunty's Revenge
In Grunty's Revenge, extra honeycomb pieces are called Hollow Honeycombs, but are still used similarly to the ones in Banjo-Tooie. Once Banjo has collected the specified amount of hollow honeycombs, he can take them to Honey B's Hive on the Spiral Rise of Spiral Mountain who will transfer them to a honeycomb container.

Extra Honigwaben