Features: (I'm making this quickly so it may be incomplete. Some features may need to be accessed through commands. Use mob_vote: prefix before trying to summon or give a mob or item.

Copper Chain
Copper Golem
Rosegold Tools

Copper Chain:
Crafted with a copper block and two ingots. Activate by having a redstone source connected then right clicking. This acts as vertical redstone.

Copper Golem:
Summoned with two copper blocks and a carved pumpkin. Presses copper buttons crafted with one copper ingot. Oxidizes over time into 'Exposed Copper Golem', 'Weathered Copper Golem', and ' Oxidized Copper Golem'. The final stage is immobile and you need to scrape it with an axe to bring it back. You can also unoxidize them by striking them with lightning. As they oxidize they get slower and weaker. They attack mobs that attack them.

Rosegold Tools:
These are gold tools but with added durability. Crafted with the new copper upgrade item in a smithing table with copper and a gold tool.