All Equipment destroyed by Omnitron

Does that mean ALL equipment IN PLAY or ALL equipment like even cards in your hand you havent played?

Destroyed is from play.

Discard is from hand.

Greywind is correct.

A card must be in play to be destroyed, which includes cards under other cards, unless those cards are specifically stated as not counting as in play (I think promo Blade says that) most cards under other cards are treated as not having text though, so they would not be equipment.  (the designation is important for a few rare occasions though)

Cards in hand or in the deck may be discarded, but not destroyed.  I only think the deck is involved if specifically mentioned, the one spite drug does that.

There's at least one environment card which says you can get rid of it if each player discards the top three cards of their deck (might be Fire in the Biosphere but off the top of my head I can't remember so maybe it's River of Lava...I have a fiery image in my head when I think of it anyway). Cards can also be discarded from the top of the environment deck when fighting Akash'Bhuta and a target from her deck either enters play or is destroyed (depending on which side she's on).

River of Lava. Had that one come up tonight :)