Based on book found in Rookgaard Libraries Pre- 6.0- Magic
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Instant spells are cast in the heartbeat they are needed and take effect instantly. Some of these spells Instant Spells heal while others are agressive and some even have more astonishing effects, such as invisibility.”
Which means first spells were to heal yourself - Exura and become invisible.- Utana Vid
On November 2001- Update 6.4 First strike spells were added to the game. From the list I can see that there is added Conjure Bolt- but no Conjure Arrow which suggest it is already in use. In addition to that Ultimate Light is added - which confirms that Utevo Lux is already in use. The other spell would be Create Illusion . Please note all those spells have “Unknown” date of release and
By looking for more information I found very epic video (if you have not seen it so far, I am sure you will love it) on tibia.com - from 3rd November 2001 Update teaser staring Knightmare, Taghor and Lady Rebel Rimule - YouTube video here.
I was not able to add list of spells from 6.4 due to exciting word limit.