It's 160 only if its owner's stadium is in play. Same deal as UNB Dugtrio, though this seems to be a sort of bigger version of that. Owner's stadium effects are strictly worse than any stadium effects like REC Garbodor. But these are still strictly better than those 'your stadium on your opponent's turn' effects like the old FCO Barbaracle (first one of those that came to mind, lol). B/c at least it's sth that you only need on your turn, so it doesn't matter how many counter stadiums the opponent plays as long as you can consistently counter their counter stadium w/ your own whenever you want to attack w/ Terrak.