Artifacts with visual effects have been added to the game.
You can buy an artifact with a visual effect for 
units from Alina in the "Visual Weapon" section.
All artifacts are in the character's inventory. Open inventory and select the last tab "Artifact". There will be all artifacts with visual effects.
Double LBM or single RBM equip the item with the effect. Next, open the skills (Alt + K) and select the appropriate skill in the "Item Skill" section. Use it and call the effect.
