So here's a random card I made a while ago

[Bringerofcake]

Hivemind Dragon
DARK
Dragon/Synchro/Effect
9/2400/2400
1 Tuner + 2 or more non-Tuner monsters
When this card battles: Neither monster is destroyed by that battle, and neither player takes Battle Damage. If a card's effect would remove this monster from the field: you can Tribute a "Hivemind Slave" you control; negate the effect of that card and destroy it. When this card attacks a monster: you can take control of it with this card's effect. Its name is treated as "Hivemind Slave" and it gains the following effect:
• If the only monster you control is "Hivemind Slave": destroy this card.

[Suibon]

[center]So what in creation is a Hivemind Slave?[/center]

[Bringerofcake]

[quote name='Suibon' timestamp='1341705895' post='5969958']
[center]So what in creation is a Hivemind Slave?[/center]
[/quote]

When this card attacks a monster:[b] you can take control of it with this card's effect. Its name is treated as "Hivemind Slave"[/b] and it gains the following effect:
• If the only monster you control is "Hivemind Slave": destroy this card.

[Suibon]

[center]Oh snap.[/center]

[center]So the Synchro gets destroyed if the only other monster you control is a Hivemind Slave? I beg your pardon, but I'm mixing up my English today.[/center]

[Bringerofcake]

[quote name='Suibon' timestamp='1341709931' post='5970035']
[center]Oh snap.[/center]

[center]So the Synchro gets destroyed if the only other monster you control is a Hivemind Slave? I beg your pardon, but I'm mixing up my English today.[/center]
[/quote]

Here's how it works.
When Hivemind Dragon attacks a monster, that monster gets turned into a Hivemind Slave. If Hivemind Dragon is not on the field, all the hivemind slaves are destroyed. If a card effect would kill Dragon, you can tribute a Hivemind Slave to negate the effect.