Unity 2D animated tiles library: IsSelected variable not working or not present within RuleTileEditor.cs

I have just tried downloading a library which will allow me to add animated tiles to unity. I have been following this tutorial:http://shadowpeakstudios.com/2018/10/22/unity-tutorial-animated-tiles/

It told me to download this library in order to work the animated tiles: https://github.com/Unity-Technologies/2d-extras

After this the tutorial told me to unzip the library and place it into my assets folder. It loaded into my assets folder and then got the following error:

Assetsd-extras-masterd-extras-master\Editor\Tiles\RuleTile\RuleTileEditor.cs(277,26): error  CS1061: 'ReorderableList' does not contain a definition for 'IsSelected' and no accessible extension  method 'IsSelected' accepting a first argument of type 'ReorderableList' could be found (are you  missing a using directive or an assembly reference?) 

Does anyone perhaps know why this error is occuring.

What is the initiative of the objects animated by the Animate Objects spell?

The Animate Objects spell indicates that the objects act on their turn, but it doesn’t explicitly state what their initiative is. Are they supposed to roll initiative using their Dex modifiers (either individually or with their size class)? This would be as in the Find Familiar spell:

In combat, it rolls its own initiative and acts on its own turn.

Or do they act immediately after the caster? This would be as in the Summon Beast spell:

In combat, the creature shares your initiative count, but it takes its turn immediately after yours.

Or does this simply require a decision by the DM?

What can an Animated Undead do to Defend Itself? [duplicate]

From the spell Animate Undead,

If you issue no commands, the creature only defends itself against hostile creatures.

A zombie is as smart as a mastiff while a skeleton is as smart as an ape.

What are some actions the animated undead might take in order to defend itself? Does it ready an attack? Does it move towards the hostiles to engage? I suggest these actions because animals of similar intelligence might do the same.

How does an Animated Undead Determine Hostility, and how does it Defend Itself?

From the spell Animate Undead,

If you issue no commands, the creature only defends itself against hostile creatures.

There are two troubling terms here, for me. One is defends, and the other is hostile.

Defends is not to my knowledge a keyword. Does the undead only take the Dodge action against hostile creatures, or does it also attempt to eliminate the threat?

Hostile is a keyword, but I’m not positive it is being used as a keyword in this situation. The keyword states

A hostile creature opposes the adventurers and their goals but doesn’t necessarily attack them on sight.

Is this the definition the animated undead is using? Must the hostility be directed towards the undead itself? Must the hostility involve an attack for the undead to take action?

The implications: An undead frequently may not need to receive a command if it plays loosely with the definitions of defends and hostile.

Do Animated Objects make Opportunity Attacks?

Do the objects animated by the Animate Objects spell make opportunity attacks?

While I believe animated objects are certainly capable of opportunity attacks, the wording “If you command an object to attack, it can make a single melee attack against a creature within 5 feet of it” makes me wonder whether additional opportunity attacks are also implicit with this command.

Heat Metal on Animated Armour – Can something be both an object and a creature? [duplicate]

Heat metal says (Emphasis mine) :

Choose a manufactured metal object, such as a metal weapon or a suit of heavy or medium metal armor, that you can see within range. You cause the object to glow red-hot. Any creature in physical contact with the object takes 2d8 fire damage when you cast the spell. Until the spell ends, you can use a bonus action on each of your subsequent turns to cause this damage again.

The target in this case was Animated armour (which is a construct).

In our session we did rule that it could work just because it fit well with the story. We played it out that the metal was melting and deforming so the joints wouldn’t work. However the issue we had comes down to:

Can something be both an object and a creature?

The armour needs to be a manufactured object for the spell to work (and it specifically mentions a suit of metal armour) but also needs to be a creature to take the damage.

Can a tarrasque be animated by negative energy flood? [duplicate]

The spell negative energy flood says:

"You send ribbons of negative energy at one creature you can see within range. Unless the target is undead, it must make a Constitution saving throw, taking 5d12 necrotic damage on a failed save, or half as much damage on a successful one. A target killed by this damage rises up as a zombie at the start of your next turn. The zombie pursues whatever creature it can see that is closest to it. Statistics for the zombie are in the Monster Manual. If you target an undead with this spell, the target doesn’t make a saving throw. Instead, roll 5d12. The target gains half the total as temporary hit points"

It does not specify the creature must be humanoid nor the size of the creature. However, it implies the new zombie’s stats must be in the MM. Can a tarrasque be animated by this spell’s effect?