Strategy:
1. Don't use 3x speed frequently (by using regular speed you will learn a lot of things, see more chances, strategies, etc).
2. No anger mode more than 8 times per wave (except u know what u r doing) 30 times per wave will make monster bulletproof.
3. Patience, no need to hurry.
4. Wrong tower position (very important), earliear towers always place it in the most wide area as possible.
5. Put some trenches in the beginning, slow, mana, poison, repeat it later, put slow trench near the most towers u have gather at one place. (U can expert traps position in Endurance mode)
6. Put tower in beginning, middle and end, it will generate more mana and stand stronger with banishment, this should be done after u have some towers located nearby altogether.
7. better 3 towers with 2nd grade in the early game than 2 towers with 3rd grade, except for armored.
8. 'Supergemming' technique, first, combine 2 different colours (it has more damage/range/etc), then add 1st grade gems with the same color. It will add gem range/damage/etc. I thought at first this tech is a bug, becoz u can't do it on gemcraft origin, but it works awesome here yay. I know this technique from margomai. But this technique will be obsolete after gem grade 9 ups (just add too little damage, waste your mana)
9. Always Try to defeat 3x XP mode first. (U'll level up faster)
10. If u got multiple same color everytime u creates a gem, the strategy is to reserve several colors in stock, use it later with bomb to change into colors u need. reserve some for later use.
Some monsters have strong/weak points against certain gems, swarm mode easy with red, combine with blue/yellow.
Carapace mode, put some high grades purple(or combination) towers gems in the beginning, and end it with smaller level gems (put higher level gems is a better way, becoz they r slow, unlike swarm)
Sudden death mode is a good practice to analyze your skill placement, tower placement and right/wrong strategy implementation.
Better use anger mode early and not at armored monsters (except your gem higher than their armor).
At some stage with Mana tap shrine and Anger shrine and Experience shrine and Mana tap shrine, u can call all waves at once(around 1500 monsters on field), use Mana tap first to get mana, Experience shrine, then finish them with Anger shrine (usually there are some monsters left) but u got around 20k mana, use it wisely.
If u play slowly, u will see more possibility and new combination, it just creatively shows up.
Try to use skill that can covers the stage condition, mostly if u use gem skill, match it with the gem that is provided by that stage.
Read original walkthrough made by Armorgames! it will help u a lot.
10. Last thing, relax, if a level too hard to beat, just leave it for a while, come back later with extreme different strategy. (^-^)
for endurance mode (for GC crazy fan only), I prefer vesperbot rather than mine, but u can try it and later will know difference
I found something interesting, this 10x speed also applies when there is no shrines, like i'm typing now while another tab play Gemcraft. U can hear the sound faster than 3X.
I put 3 colours gems, it has amazing result.
Red-blue-purple Red gem (+5 monsters hit, only after grade 5) add with blue and shock (put it in the most intersection with most towers). Lol, the monsters just stop in the trap (becoz it has slow and shock)
Yellow-red-orange grade 8 in traps, put it in the L path (i mean corners, becoz yellow add range so much, it will be a little useless if u put it in straight lines.
U will need all types of gems, purple (becoz later their armor will be very high)
I put slow every 2 tiles.
when i put grade 4 shock in traps, it says 17% chance to shock, when i add grade 4 re gem, it says 10% chance to shock but with +5 monster (so it's about 60%) in an area full of monsters yay
don't anger swarm too much, it has lowest score gain (with the highest trouble gain lol) becoz it lets the slower monsters to banish.