This Walkthru is for the HERO level (although it can be used for any level) of version 1.2 of the game.
After arriving on the Isle, go west(left) to get a strength potion, then go east(right), back to the resort to get the rope from the basement of the first house (far top corner in basement) and a latern from the basement of the Inn (just next to the basement steps).
Go to the well, talk to the people in it to get directions to the currator's house (there's no point using the rope to go down yet as you're not strong enough to get the sword from the man. Go to the currator's house (SouthEast corner of the Isle), don't bother saving the girl yet, or talking to the old woman (she's just story padding, talk to her when you have magic and she changes into a wizard who laughs at you and runs away). Get the gold heart in the barrel near the entrance to the temple (bottom of screen). Into the currator's house, get the defense potion, and read the note to get 27 gold pieces. Now go back outta the house and up a screen and kill all the pillbugs, get the strength potion from the chest, back down and then west to the magic mushroom circle/fountain, hit the largest mushroom (without taking on the slayers) and, hey presto, a secret opens which warps you to the magic potion on the little hill. Walk forward from this and you're warped to the NorthWest of the Island - the blocked off mine.
Go South a couple of screens to find another gold heart in a chest, then East to the Church. Drop a couple of coins in the church fountain and get your life to max. Now back up to the Resort at the top of the Isle. Go down the well now and talk to the man, he will give you a sword. Go up to the surface and head back to the currator's house, read the note again (now that you have magic you will be given the fireball spell). Back out and up to the NorthWest corner of the Isle again to burn those trees standing in a ring outside the blocked off mine. Open the chest in the middle of this ring to get the throwing axe. Now things are a little easier.
Go East to save the girl, just stand at a distance from the zombie/stone monster and throw the axe at him. Try not to hit the girl, if you kill her you cannot win the game. Once the monster is killed, go to the girl, talk to her and then you are warped to the church. Little movie about the blacksmith who has moved down to the underground village. The Father gives you Aldus' scroll. Now go back to the slayers and take them out (to get gold ... as much as you can). If you're feeling good, go down the hole next to the well to get some goodies (potions and hearts) but there are a couple of zombies to watch out for. You can also get hearts down the hole in the grassy grove under the cess pit (just west of magic mushroom circle). And if you're up to it the rooms in the inn have a variety of goodies for those willing to try battle the zombies there. There are three chests each with 5,000 gold pieces, a throwing axe, a couple of all-purpose potions, a gold heart and a scroll for hellfire magic spread across the six rooms. Also the dragons in the Northeast corner of the Isle are guarding 5,000 gold pieces.
Now before going to the Old Gold mine, go to the deserted village, down to the SouthEast corner to the armourer store - door on the right is unlocked - and enter. Press space bar at the potions bookshelf to make at least three bombs and go back out.
Now onto the old Gold Mine - go back to the Church, South to the Cemetary, East passed the mess of slimers, and East again to the bonca's kill 'em all, get their goodies and then push the rock from the left side. Down the hole and then plant a bomb next to the rocks blocking your path.
Bam! Now over to the right and plant another bomb to get the gold heart behind to rocks in the corner there. Then thru the door, into the deserted house and through the next door and follow the path around to the village.
Now if you haven't got 5,000 gold pieces yet you can get that at the casino (upstairs from the bar) if you have 750+ gold ... by first getting the barman drunk on whiskey. It takes him ten drinks before he tells you to play the dice game, and WINKS. Now when you go upstairs you can just tell the guy playing dice that the barman sent you and hey presto you automatically win 5,000 gold pieces.
A quick note about the rest of the village ... the potions lady can heal you, and sell you potioins - the effects of these potions can be either bad or good, if you've got gold to burn try the 6,000 one, if you're lucky your strength, magic, defense stats should jump up by 15 (or 20 I can't remember). But keep 5,000 gold aside (for the blacksmith). The girls in the brothel are just there for diversion. The highest price girl (Jenny - 5,000) is the best ... you have a 2 in 3 chance of getting laid and having your strength, defense and magic all go up by 10, plus heaps of experience points which should take you up to level 13 - just go out and kill some monsters. Worth doing in preparation for battling the wizard at the end. The weapons store can sell claw-swords, lanterns etc incase you feel a need for any of these.
Okay ... down south of the village is the entrance to the mines. There are a number of hearts, all-purpose potions around, plus one secret chamber: this is SouthEast of the mines, with the entrance blocked by a rock, use a bomb to open it up and go down to get lots of potions and hearts. Then back up North to find the blacksmith ... he will appear eventually in either the top left of the mines or the 2nd screen down on the top right hand side. (it's a random thing, just enter and exit the screen until he appears, you'll know when, as the load time will increase) When the blacksmith appears, talk to him and he will take your Aldus scroll, 5,000 gold pieces and make you a light sword.
Now is the time to make yourself as strong as possible. Kill as many monsters as you can, visit Jenny or dabble in potions (whatever your choice is) to get your stats up. (Go back to the inn in the resort if you haven't cleaned out the gold there, or kill all the dragons at the NorthEast of the Isle to get another 5,000 gold from the chest). Basically get your magic, defense etc to at least 20.
Now outta the mines/underground village and then head East to find pillbugs/slayer and a couple of dead bodies. Kill the monsters and then search the dead body lying down from a crater with water droplets. You'll find a note about the currator's water magic. Now go back to the currator's house and go the top right hand corner, when you touch the wall it moves aside to reveal stairs. Up the stairs and you're in the library. Read the books in the far right bookshelf to find the currator's journal. Now (if your magic level is high enough, if it isn't go out and kill so more people) you get given water magic. Okay, back down and into the temple.
Kill the zombies in the temple, get the potion in the bottom left corner, search the potions in the shelves and take a drink (You stand a pretty good chance of increasing your magic). Now hit the machine with you light sword and you can enter the underground caverns leading to the wizard. Now you've lost your light sword, so arm up with axe and water magic. Make your way through the caverns killing all you can, get to the save machine and kill all the zombies, save your game and then head North to kill a few more zombies, get 3 potions in the far left corner, back to the save machine, head East and kill more zombies, get 4 potions (plus there is an exit here to the surface - the place marked X), back to the save machine, save your game and then head south. Kill zombies again, get final gold heart in chest behind creepers/thorn bush in NorthEast corner, use red heart to max your life and then through the portal.
End Game - let the wizard talk and then hit him with water magic as soon as you can. It strips him of his defenses and strength (which are pretty high at HERO level, not so high at other levels) and as soon as he throws his last spell at you hit him with the axe and you've won. If you hesitate, and he gets a couple of spells out you could still die.
Hope you've like this D-mod.
NB. In other versions of "Isle of Croth" you get to the underground caverns that lead to the wizard by going down the hole in the centre of the village. In version 1.2 if you go down this hole there are zombies to kill, and then the wizard taunts you and blows out your lantern. But you can always get another one at the currator's house.