Red gems are one of the 8 gems(GC1,GC0,GCL) 10 gems(GC2) of the gemcraft series. Its abilities are Splash, which lets the target hit multiple targets around it, Bloodbound, which makes the gem gain more damage from enemy kills, and the Chain hit, which was from the removed Lime gem, allows the gem to hit multiple targets in random positions near the main target. The Chain hit ability is similar to the splash ability.
In Chapter 1,Chapter 0 and The IOS Version red gems have a special called "Splash Damage". This allows the gems to hit multiple targets around it at once. This Ability is similar to the Chain-hit ability, except it makes a chain around the target.
In Gemcraft: Labyrinth red gems no longer have splash damage, but a new ability called "Bloodbound". This makes a gem gain more base damage, depending on how many kills the gem has had.
In GemCraft Chasing Shadows, red gems are now Chain Hit, as the lime gem is removed, letting them hit extra enemies near the target. The Bloodbound ability has been given to the Black gem.
In traps, red gems can hit multiple targets, especially with red mastery maxed out, although the actual maximum number of targets does not appear with a splash radius below around 15.
Combine a red and an orange gem and place it in a trap to get a gem that hits rapidly and gains mana with each hit. or red and blue for mass slowing, red/green for mass poisoning etc.
Place red towers near the start of the level to hit the clumps of enemies at the beginning of the waves.
In Gemcraft Labyrinth, Bloodbound gems can be used in many levels to get extremely high scores. Set map settings to double Armored-only monsters(and perhaps additional difficulty), set up a single max-grade Bloodbound gem at a strategic point, and surround it with amplifiers as mana permits. On most maps, the gem's damage grows as fast as monster HP or faster until about wave 40, and even with early waves and heavy summoning it can mow down whole waves unassisted. 6-8x base XP is usually quite attainable with a decent wizard level if you get some battle amulets.
Gemcraft Chapter 1Edit
Gemcraft Chapter 0Edit
Gemcraft Chapter 2Edit
It has a chain hit length of 1.18 at g1 and 2.79 at g12 without any boosts