Customization in TERA comes in many forms. At level 25, players in TERA can customize their skills with Glyphs. Every glyph increases a skill’s effect; glyphs of Influence and Brilliance help skills cost less MP; glyphs of Energy and Persistence give skills shorter cooldowns; glyphs of Lingering increase skill durations. There are hundreds of glyphs for hundreds of skills, each of which has one to four different glyphs available. City glyphmasters provide them, but you decide whether to activate multiple glyphs on one skill or spread your augmentation over many skills.
One sorcerer may focus all her glyphs on speeding up access to and boosting the power of her favorite skill (Blazing, Impelling, and Empowered Fireblast), while another focuses on reducing downtime on all her skills (Energetic Overchannel, Blazing Fireblast, Energetic Void Pulse).
Whether soloing or tanking, lancers may find defensive combos advantageous. Pumped Stand Fast, Influential Stand Fast, plus Threatening Shield Counter give a lancer facing a big-ass monster extra damage with more aggro for less MP cost.
Slayers capitalize on knocking the enemy down. Persistent Overhand Strike, Restorative Overhand Strike, and Stunning Knockdown Strike provide a slayer the means to be more effective more often.
For healers in party play, most focus on healing themselves first (Restorative Heal Thyself or Energetic Thrall of Life), then everyone else second (Multiplicative Focus Heal or Blazing Arun’s Tears and Arun’s Vitae).