Orcish Squatters

Whenever this creature attacks and isn't blocked, you may gain control of target land defending player controls for as long as you control this creature. If you do, this creature assigns no combat damage this turn.

Masters Edition II

Whenever Orcish Squatters attacks and isn't blocked, you may gain control of target land defending player controls for as long as you control Orcish Squatters. If you do, Orcish Squatters deals no combat damage this turn.

Fifth Edition

o0: Gain control of target land defending player controls as long as you control Orcish Squatters. Orcish Squatters deals no combat damage this turn. Use this ability only if Orcish Squatters is attacking and unblocked and only once each turn.

Ice Age

If Orcish Squatters attacks and is not blocked, you may gain control of target land controlled by defending player. If you do so, Orcish Squatters deals no damage in combat this turn. Lose control of that land if Orcish Squatters leaves play or if you lose control of Orcish Squatters.

The ability triggers on the declaration of blockers if no blockers are declared for it.

If you lose control of Orcish Squatters before its ability resolves, you won’t gain control of the targeted land at all.

An ability that triggers when something “attacks and isn’t blocked” triggers in the declare blockers step after blockers are declared if (1) that creature is attacking and (2) no creatures are declared to block it. It will trigger even if that creature was put onto the battlefield attacking rather than having been declared as an attacker in the declare attackers step.