wOW
===
This is the most visually incredible ZX81 game i have ever seen:
* Pixel-perfect hi-res graphics
* Perfect fonts in hi-res mode during gameplay
* Jumps in and out of hi-res seamlessly (setup screen and hiscore screens are lo-res)
* Uses the standard ZX81 fonts right in hi-res screens!
Compared to other ZX81 pseudo-hires games from the 1980s, this looks more polished. Game play is also OK. But look at those beautiful graphics! Now if someone could add sound to this game it reminds me of 1983 and the first time I played defender. It was on an Apple II and the looks of this ZX81 game have brought back memories
The tape cover said "ZX-81 Resolution identical to SPECTRUM without any additional hardware!!".
At Pound 5.95 in 1984 (including shipping) it was reasonably priced
GAMEPLAY
========
The game starts by helpfully listing the keys used. And lets you re-define them if you like
The goal is to extricate your men while avoiding aliens and trying not to crash upon the mountain terrain. When you see a man, move down over his head to pick him up. DANGER don't hit the ground
If you eliminate any if the three types of aliens, you get 5 points? The machine code suggests to me that for every four aliens you get a bonus. The action is fierce so I haven't been able to observe if that's exactly what happens. The three types of aliens move in ways that remind me of Galaxian. They are moving in pre-choreographed patterns. Because there are up to three types of aliens mixing it up on screen at the same time a pattern is not obvious to me
Game play is good, and controls are responsive. Does the game hold interest over the long-term? I dunno, i'm not much of a game player and haven't been able to advance to WAVE 2 ...
HI-SCORES are taken. Save the tape to save them and when you re-LOAD the updated scores will be there
North America ZX81
==================
Xtricator runs on a 50hz ZX81. If run on a 60hz machine the TV picture will roll. It can be modified version to work on 60hz, by changing one byte. Provided below -- plus it bypasses the two-LOAD procedure (downside: the glorious Cosmic Cockerel splash screen does not appear)
I suspect on some TVs the display will be cut off on the left side unless horizontal hold is adjusted. Let me know how it works on your TV
TAPES
=====
The version at ZX81 Collection appears to be true to the original (xtricator.p) and shows the splash screen
The version at The Software Farm Tribute Page (ZXTR.P) doesn't show the splash screen, but still requires the two-LOAD process. All that work for no payoff (I want my screaming chicken!)
Apparently the first version crashed on newer ROM, however the two versions above work fine with all three ZX81 ROM versions
EMULATOR
========
Xtricator runs fine on EightyOne emulator
Set the hardware on the Options menu:
* 16K
* WRX off
* 50hz (60hz option unchecked, otherwise the screen rolls)
1. load xtricator.p. After loading it will flash the screen as if waiting to load a tape
2. On the EightyOne Options menu, click Tape Manager
3. IMPORTANT: Uncheck the "Auto LOAD on insert" button
4. Click the Open Tape File button (open folder icon) then open SCREEN.P
The Software Farm splash screen appears. Press any key to continue
NOTE: because Z-Xtricator overscans the display, with Eighty-One the picture is cut off on the left unless a substantial screen border is used:
1. On the View menu, click Border Size
2. Select Normal, Large or Full Frame
Z-Xtricator uses a 32-character display but the it seems the timing is causing the picture to shift slightly. This was common on old TVs. The picture is shifted one character (8 pixels?) to the left
All in all, I give it a 10/10 for Sinclair ZX81 game
[edit: added the year (1984) to the title]