Controls the High Level Abilities (HLA) available to each kit. A maximum of 24 abilities can be shown on the HLA screen.
The first column is a numeric identifiter.
The second column lists the filename of the spell involved, prefixed by GA_ (Gain Ability - the spell is given to the character) or AP_ (Apply spell - the spell is cast on the character).
The third column may represent the icon to display for the abiltiy on the HLA selection screen. How this interacts with the icon as specified in the HLA itself is unknown.
The fourth column may represent the text to display for the ability on the HLA selection screen. How this interacts with the text as specified in the HLA itself is unknown.
The fifth column is the minimum level the character must be to be able to select this HLA.
The sixth column is the maximum level the character must be to be able to select this HLA.
The seventh column indicates the maximum number of times this HLA can be selected by a character.
The eighth column lists prerequisites, i.e. the listed HLA (if any) must have been selected before this HLA can be selected.
The nineth column shows an exclusion HLA. If a HLA is listed in this column, either the listed HLA or this HLA can be selected - but not both.
The tenth column lists an alignment restriction (align.ids) - only characters with a matching alignment can select the HLA.

Note that the engine stops parsing the file at the first line containing only default entries (i.e gaps cannot be left in the entry list).

In BG2 ToB we have (luba0.2da):

2DA V1.0
*
           ABILITY    ICON       STRREF     MIN_LEV    MAX_LEVEL  NUM_ALLOWED PREREQUISITE EXCLUDED_BY ALIGNMENT_RESTRICT 
1          GA_SPCL910 *          *          1          99         16          *            *           *                  
2          GA_SPCL911 *          *          1          99         16          *            *           *                  
3          GA_SPCL912 *          *          1          99         16          *            *           *                  
4          GA_SPCL913 *          *          1          99         16          *            *           *                  
5          GA_SPCL914 *          *          1          99         16          GA_SPCL913   *           *                  
6          AP_SPCL915 *          *          1          99         1           *            *           *                  
7          GA_SPCL917 *          *          1          99         16          *            *           *                  
8          GA_SPCL918 *          *          1          99         16          *            *           *                  
9          GA_SPCL919 *          *          1          99         16          *            *           *                  
10         AP_SPCL920 *          *          1          99         1           *            *           *                  
11         GA_SPCL921 *          *          1          99         1           *            *           *                  
12         *          *          *          *          *          *           *            *           *                  
13         *          *          *          *          *          *           *            *           *                  
14         *          *          *          *          *          *           *            *           *                  
15         *          *          *          *          *          *           *            *           *                  
16         *          *          *          *          *          *           *            *           *                  
17         *          *          *          *          *          *           *            *           *                  
18         *          *          *          *          *          *           *            *           *                  
19         *          *          *          *          *          *           *            *           *                  
20         *          *          *          *          *          *           *            *           *                  
21         *          *          *          *          *          *           *            *           *                  
22         *          *          *          *          *          *           *            *           *                  
23         *          *          *          *          *          *           *            *           *                  
24         *          *          *          *          *          *           *            *           *                  

Description applies to: