Terrarium Terrarium v0.1 Beta 1

The 1st beta for Terrarium.

View all changes in detail in changelog.txt.

For a quick summary, see below:

- Added Voidllagers, hostile illagers that naturally spawn on End Islands.
They spawn with a variety of 4 Shulker Shelmet colors.
Disguise yourself as a Voidllager by equipping a Shulker Shelmet when out of field of view.
Once disguised, you can now barter with them with amethysts. When given enough amethysts and satisfied, they will drop a variety of different loot.

- Added Shulker Shelmets, dropped by Voidllagers, they give +2 Armor and +1 Knockback Resistance.

- Added Voidllager Spawn Eggs.

- Added Weather Globes.
Right-click to suck in the current weather, right-click a filled globe to release the stored weather and change the weather for 5 minutes.

- Added advancement, "Alone in the Abyss".
Earn it by killing a Voidllager.

- Added advancement, "Headspace".
- Earn it by equipping a Shulker Shelmet.

Added advancement, "Mad Hatter".
- Earn it by collecting all 4 variants of the Shulker Shelmet.

Added advancement, "End Exchange".
- Earn it by successfully bartering with a Voidllager.

Added advancement, "Rain Rain Go Away".
- Earn it by using a Clear Weather Globe while it's raining or thundering.

- Added gamerule, "doCustomMobSpawning".
Defaults as on, toggles if custom mobs spawn.