SC2Mapster

I would use an automatic Morph type ability validated by a Unit Compare Kill Count validator. For the colour change you could use a Simple type actor that is created when the Morph abilities are used and on actor creation targets the ::Main reference using a Set Team Color actor message.

The Morph type ability changes one unit type into another. An example is the Burrow ability used by many zerg units. Under this ability is a flag called Automatic that makes the ability instantly use itself when the costs, requirements and validators are met.

Validators is a data type and under it create a new validator of the type Unit Compare Kill Count. Set the Validator: Compare field to Greater Than logic and the (None): Value field to the number of kills you want.

Put this validator under the Ability: Validator Array field of the Morph ability. There is then the Stats: Flags field which has the Automatic flag.

As mentioned to chance the colour you need to send a Set Team Colour actor message. This can be done using actor events or triggers. As stated earlier having a Simple type actor is the easiest method but you could also add an event to the Unit type actor of the unit you morph into using an Actor Creation event that uses the Set Team Colour action.

Do the two units cost different amounts? If so you also need the Ignore Unit Cost flag.

Again the Autocast and Autocast Initially On flags are under the Stats: Flags field of the Morph ability. Still automatic has the same effect.

More likely the actor not being destroyed when the ability finishes. You need to add some actor events to destroy the old actor and create the new one on morph completion.

Under the Actors data type there are Unit type actor for both units you will find several fields starting with Events (eg. Event: Events - Send field). Double click the field to open another window.

Right click the left panel of the window and add a new event. Use an Ability Morph message type and Start subname with a Morph From term and a Destroy actor message. On your warpig actor use an Ability Morph message type and Finish subname with a Morph To term and a Create actor message.

Can you find the actor events first?

Press the green + at the top of the data editor to open the Actors data type. Find the actors for your Marine and Warpig and find the events fields. Double click them to open another window.

Can you find the Actors data type under the data editor. It has a picture of a yellow Zergling as the icon. The editor should default to having the Units data type open and to the right of that tab is the green + icon.