Gem

Gems are a shameless money-grab currency-slash-power-source from the Angry Birds Transformers series.

Shiny! Found on Piggy Island, Gems are shimmering blue crystals that can really turn the tide for their owners. They can power up robotic bodies, recharge lost energy, and so much more.

Games

Angry Birds Transformers

Gems are the "premium" currency of the game, and anyone semi-familiar with "free to play" games is already groaning. Gems are very powerful, and can really upgrade your characters super-fast, where other methods can mean hours or even days of not being able to do anything with a character until the process is complete. The game is designed to be a grind without spending Gems.

Earning Gems

It's actually not hard to earn Gems. There are a lot of places to get them, and the game often just hands them to you for free. But, it is by no means a quick process. Just as the game is designed to be a grind without Gems, it's designed to be a grind to amass large numbers of Gems unless you take one specific action...

• Daily Prizes — Gems are two of the seven Daily Prizes, awarded for simply booting up the game once every 24 hours. There's one for 5 Gems, the other 10. Once a "cycle" you can watch an ad to double your prize, so save that for the 10-Gem package. Note that prizes will not "stack": you have to claim one prize before the 24-hour countdown starts to claim the next one.
• Chests — Occasionally, one to three Chests will appear on the game map (usually in the southwestern area), each one containing 1~6 Gems to be picked up for free. Of course, the number of chests and their yield are weighted toward lower numbers.
• Jenga Stage — Every couple of days, the prize for amassing enough Jenga points in a day changes from 3000 Coins to 10 Gems. The 300-point goal for the prize can usually be accomplished in 4 to 5 runs, pretty easy.
• Daily Quests — The eight random Quests (and one fixed "finish all the others" Quest) you are presented with every 24 hours have the chance to offer Gems as prizes, seemingly maxing out at 10 Gems per Quest. Of course, some days you might not be offered any Gems. Sorry!
• Achievements — Similar to the Daily Quests, these set 86 tasks are once-only affairs, but they all give up Gem packages, from 5 to 20 Gems depending on difficulty. Some you'll just hit naturally playing the game normally. Some, though, directly cost Gems to accomplish, and these cost far, far more than their reward, so why bother?
• Space Bridge Missions — Each Space Bridge has the chance to offer Gems as one or more of the mystery prizes in their Missions, with higher odds of higher Gem packages in the longest of each Bridge's three missions. Your best bet is to always shoot for the longest mission per Bridge, after all, you'll always earn at least one Key (two for watching an ad).
• Pig Lab — Every combination of Materials you can toss into Professor Pig's contraption has a chance to come out as a Gem prize. The more valuable the Materials, the more Gems you might get (thanks to the randomized nature of the actual outcome).
• Just buy the damn things with real money — Yeah. The game allows you to buy hundreds of Gems in packages with real actual legal tender. Packages range from 150 for $4.49 US to 5200 for $89.99. We're not making that last one up.

Gem packages were offered twice as part of some Challenge Events, but that's only twice out of the nearly two dozen Events that have happened since the time of this writing.

Spending Gems

This game really, really wants you to spend Gems willy-nilly. It gives you a lot of opportunities to drop Gems. Because then when you're short Gems for that thing you want, you're tempted to toss some actual-factual money at the game for Gems. And yes we're gonna list them all because we're like that.

• Changing stage characters — For a single Gem, you can change what character is assigned to a stage to another randomly-chosen character. This is really only "useful" if the current character is unavailable due to an Upgrade, Repair, or Mission, and you're impatient about clearing that stage.
• Instant unavailability completion — Or, if the above method for some reason doesn't seem reasonable, you can spend Gems to have the thing that's keeping them unavailable instantly finished. The longer the timespan you're cutting short, the more Gems this costs.
• Interrupt Eggbot cyberforming — New stages take varying amounts of time for the Eggbots to finish. Spending Gems will make the stage instantly available, and plop an Eggbot onto the player's path that they can shoot for extra Coins. The more time that was on the clock, the more Gems. If there's a relationship between Gems spent on how many Coins the Eggbot may drop, we don't know it because we sure ain't spending the Gems to find out.
• In-stage recovery — Should the badguys get the best of you, Astrotrain will grab you with a tractor beam to pull you out. However, there's a six-second period where you can drop 10 Gems to instantly and fully heal, and get back to the action. The question is: will this be this worth it? (The answer is "rarely if never".)
• Instant Upgrade/Repair — This is like the stage-based shortcut above, only you do this from the Barracks screens. Upgrades you can spend Gems for an instant level-up, rather than spending Coins and Materials and waiting however long it takes. Armor repair, you have to start the repai process with Coins, then click again to spend Gems to instantly end the process (though really just watch an ad it's 30 seconds you can go do anything else in for a free repair).
• Customizing — Every character has multiple Accessories that improve their stats, and every one of them costs Gems. Some, like common baseball caps, sunglasses and headphones, give small boosts and only cost 25~50 Coins. More character-specific Accessories that imbue much more powerful buffs, however, run from 300 to 1000 Gems. These prices are often slashed during Challenge Events, so the Gem cost is equal to the Token cost (see below).
• Send more characters on Missions — The Easy Bridge allows you to send two characters into a Mission, while Medium and Hard only allow one each. You can drop Gems to send more characters along, up to three per Mission. However, the cost is 100 per extra character on Easy and Medium, 200 on Hard. Frankly, no prize they can offer is worth that.
• Open more Mission prizes — Space Bridge Missions are rewarded with up to five keys, which open five boxes with shuffled prizes inside. If you really, really want a prize from the wheel but have run out of Keys, you can spend Gems to open more boxes: 10 for Easy, 20 for Medium, and 30 for Hard. This is really only worth it when the prize is a new character (which doesn't really happen so much anymore) or if you've got say 3 or 4 Keys and didn't get that character or Super Rareium you really need.
• Re-spin the Pig Lab prize — When using the Pig Lab, you have a 1 in 5 chance of getting the item you want. If you don't get it, you can spend 10 Gems to re-spin, minus the item you got the first time (which is completely discarded), then 20 for another spin, etc, doubling every time. Really only "worth" it, and that's very debatable, for the high-rated Energonicons that cost Super Rareium to make since that stuff isn't all that easy to come by.
• Recharge Challenge Mission batteries — Challenge Mission energy recharges at one "battery" per hour, and caps out at four. You can instantly recharge all four batteries at the cost of 10 Gems... then 20 for second charge, then 40, etc. The amount re-sets to 10 with the start of a new day in the Event. This is one case where the cost could easily be justified, at least early on, since extra four rounds can provide a heavy score boost and a lot of Tokens, and buying Accessories with Tokens is almost invariably a far better deal. Watch your timers though: if you're close to a "free" recharged run, wait, and if you're only 5 minutes away from the end-of-day, consider if you can actually use all four runs in the time left (probably not) and how many Tokens you may or may not earn for your Gem cost.
• Buy missing Tokens - Not got enough Tokens at the end of a Challenge Event for that prize you want? You can make up the difference with Gems, at a cost of 1 Gem per every 2 Tokens. In most cases you were better off spending the Gems on a battery recharge.