Hardened Mox

Hardened Mox
UnitMech SoldierCost: 3ATK: 1 HP: 1
Indestructible (If this would die, exhaust it and remove all damage and attachments from it instead. You can't sacrifice it.)
When you have a tech II unit (even a forecasted one), trash Hardened Mox.
Purple Tech 0

Card-Specific Rulings
You only have to trash Hardened Mox if you have one or more tech II units in play and/or forecasted. It doesn't care about Tech III units, Tech II buildings or upgrades, or units in Jail/Graveyard. — Sirlin
Indestructible Rulings
If an indestructible thing has 0 HP because of having -1/-1 runes, it will remain exhausted forever. If it gets any damage or attachments in this state, immediately remove the damage and/or attachments. — Sirlin
Attachments are cards that attach to a unit or hero, like "Spirit of the Panda" or "Entangling Vines". Runes and other ongoing spells or effects are not attachments. — Sirlin
Even if it has -1/-1 runes that were from something that "dealt combat damage in the form of -1/-1 runes," you still don't remove them when the indestructible thing would die. — Sirlin
Some effects like Obliterate, Sacrifice the Weak, and Death Rites ask a player to destroy or sacrifice the unit that is the least according to some ordering. These effects skip units with Indestructible and units that cannot leave play. — sharpo