Unrelenting - Exhaust this card after resolving an attack with a Melee weapon with 1 hand icon. Perform an attack that targets one of the same monsters with a different Melee weapon with 1 hand icon.

CCRG - The monster targeted with Unrelenting must have been a target of the attack used to trigger Unrelenting.

When the initial attack is from 2 spaces away with a 1 hand weapon with reach, is it allowable to hit the same monster with a different weapon that doesn't have reach for the Unrelenting strike?

I am assuming no, otherwise the wording could be manipulated to say the range on the second strike is irrelevant altogether since it doesn't indicate positioning at all. Or are skirmishers so unrelenting that they can hit anywhere with this ability? I am just thinking if there are cards that allow monsters to move after a strike resolves that might come into play also. Dunno if those exist.

No. Just because an ability lets you perform an attack doesn't ensure that a monster is in range to be targeted by that attack.

Those abilities exist (moving). Think about a Orkell's hero ability if he's attacked by a melee monster and the OL plays Flurry. If there isn't another hero around, Flurry is a waste.

No, but you can spend a fatigue to move closer to the target.... or can you?

Not after you've declared an attack, no. There's no window between the first attack and the exhaustion of unrelenting where you could move. Unrelenting would be exhausted right at the end of the first attack.

Surge on a Trident, gain 2 move points, can they be used before the Unrelenting strike?

1 hour ago, NewKevlar said:

Surge on a Trident, gain 2 move points, can they be used before the Unrelenting strike?

Nope. Having the MP isn't the issue, it's having the time window to spend them (which doesn't exist).