Two Step

Ongoing Spell — Buff • Cost: 2

Channeling (Stays in play. Sacrifice it when you lose your Finesse hero.)
Two of your units become dance partners if they aren't partnered already. While you control both, they each get +2/+2. If you lose one, sacrifice Two Step.

The two units had a special time together.

Neutral • Finesse Magic

Card-Specific Rulings

If a unit is already a dance partner from Two Step, you can't legally target it by playing another Two Step. — Sirlin, 03/02/16

"If you lose one" means if one of your partnered units leaves play or leaves your control. — Sirlin, 03/04/16