Shield
Shields are throwable snowballs that place a 7x7 upright disk of glass and glass panes (colored respectively to the team of the thrower) wherever they end up after 1 second of uninterrupted flight. Unless broken or exploded, the Shield remains on the map until the arena is cleared.
Use Cases
Shields are very useful for stopping missiles. When a Shield is thrown in front of a missile, it presents an obstacle that the missile may not be able to pass through due to the 12-block piston push limit, forcing it to stop and (if not already disarmed) detonate and explode.
Note that the above does not always work if the missile has Shield-busting properties, or otherwise, if there are enough blocks removed from the missile for it to continue safely through the Shield. A better technique in this case is to throw the Shield inside of a missile in flight so that it may replace some critical blocks (pistons, slime blocks, observers, etc.) and thus render the missile immobile.
Shields also block arrows, Fireballs, Nova Rockets, and similar projectiles from hitting the player or a missile.
In a similar vein, a Shield may be thrown in front of a Canopy ender pearl to prevent the Canopy from spawning, or thrown in front of a player who is about to jump onto a missile to prevent that player from making the landing.
When thrown inside of a Vortex, a Shield occludes the Vortex and forces it to explode. Also, when thrown inside the log of a Canopy, the log breaks and the leaves rapidly decay, thus shortening the Canopy’s duration.
Similar to arrows, the Shield snowball projectile can be used to launch or deflect Fireballs.
Shields can also be used to protect and reinforce damaged areas in the base if thrown against the wall. Moreover, the top of a Shield can afford solid ground and protection to a player away from their base.
Through a technique known as “Shield-stacking,” several Shields can be thrown on top of each other and mined into a staircase that gives players significant upper ground. Shields may also be thrown downwards to allow players to “low-ride,” or travel on missiles beneath the usual playing area. (Although ill-advised if you wish to be a good sport, these are both undeniably valid strategies.)
Shields cannot be used to break portals.
Gamemode Specific Behavior
In Powerups Mode, Shield snowball projectiles can be used to deal knockback to Bees and set off End Crystals.