When playing [Silent Hallcreeper] as a singular creature, the game loops when it should ignore an activated ability.

[Silent Hallcreeper] has the following ability:

> This creature can't be blocked.
> Whenever this creature deals combat damage to a player, choose one that hasn't been chose -
> * Put two +1/+1 counters on this creature.
> * Draw a card.
> * This creature becomes a copy of another target creature you control.

However, if there first two are already chosen AND you control no other creatures AND the last available ability is `This creature becomes a copy of another target creature you control.` the game engine goes through an infinite loop, unable to actually cancel since the rules dictate all abilities can only be used one time.

Furthermore, the rulings on the card specifically deal with this:

> If the third mode is chosen for Silent Hallcreeper's last ability but the target creature is an illegal target as the ability tries to resolve, it won't resolve and none of its effects will happen.

[Ref #1 of rulings](https://gatherer.wizards.com/DSK/en-us/72/silent-hallcreeper)

## Expected Outcome:
- Game engine allows the cancel, the ability does not resolve and none of the effects happen.

## What currently happens:
- Game engine goes through an infinite loop of "cancel".

## Client information:
**XMage Launcher version installed:** 0.3.8
**Java version installed:** 1.8.0_201
**XMage version installed:** 1.4.58-dev (2025-10-06 20-40)